Holiday shopping season is upon us, and more than a few folks will be buying replica Nationals uniform jerseys for the baseball-crazy fans on their naughty-or-nice lists. There’s nothing like a successful season - a second National League East title and playoff appearance in three seasons - to jack up sales in the official team store or via your favorite Major League Baseball-approved website. There are few things more American than baseball, apple pie, Chevrolet - and the ringing of cash registers.

One of my favorite online stops is Ebbets Field Flannels, the Seattle-based company that deals in authentic retro baseball wear (OK, they do hockey and football, too, but balls and bats are their bread and butter). One of my favorite traditions is to use my Rotisserie baseball winnings to purchase a new Ebbets Field Flannels jersey. A Santurce Cangrejeros jersey commemorated a championship by Pedro’s Cangrejeros a decade ago and a Mexico City Red Devils jersey marked the title by Los Diablos Rojos two years ago.

The last couple of seasons, we won’t talk about, OK?

Something caught my eye on the company’s Facebook page overnight, a post showing what they think could be “the rarest MLB uniform ever.” It showed a guy posing in a 1970s-style uni (easily dated because it looks like it could have been period slo-pitch softball get-up) with “Washington” in white-outlined red letters arcing across the chest and a block W with a star atop it on the tri-paneled cap. The model is a long-ago pitcher named Dave Freisleben, and he’s part of Washington baseball history, even if a lot of newer fans probably don’t know the story of how he came to have the name of the nation’s capital on the front of a gray jersey with red, while and blue piping that never saw the light of a major league day.

In the Rule 19 Blog on its website (named for the regulation outlining players’ attire), Ebbets Field Flannels happily recounts the story of the 1974 San Diego Padres, otherwise known as the team that got away from Washington, D.C., during the city’s hiatus from the major leagues from 1971 to 2005, when the Expos arrived from Montreal and were rechristened the Nationals.

In the six seasons after expansion awarded San Diego a team that began play in 1969, the Padres were the definition of a struggling franchise. They’d never won more than 63 games, had lost 100 or more games four times (and 99 another) and were in big financial trouble. Owner C. Arnholt Smith, a banker with ties to President Richard Nixon, was being sued by the Internal Revenue Service and wanted to divest himself of his headache of a ballclub. Never mind that they had 15 more years on their lease at San Diego Stadium or that Washington had lost two major league franchises in the previous 15 years; the embattled Smith struck a deal to move cross-country to Washington’s RFK Stadium. The proposed relocation got the blessing of the National League and baseball-starved fans in D.C. rejoiced.

A tentative schedule for 1974 had the new Washington entry opening the season at home against Philadelphia (it’s not known how the powers-that-be would have accounted for the Padres moving to the East Division by moving an East team the the West Division). Topps even printed baseball cards for 1974 showing former Padres players, still in the mustard-and-brown duds of the Swinging Friars, with their team listed as “Washington Nat’l Lea.” (I distinctly remember crossing that off in ink and renaming them “Padres” whenever one of those interlopers appeared in a wax pack.) Smith had accepted a downpayment of $100,000 from a ground of D.C. businessmen headed by Giant Food owner Joseph Danzansky and appeared poised to sell his club for $12 million.

The new team apparently would have been called the Stars - hence the celestial adornment on the non-curly W on the cap. Not sure how this would have played in D.C., where one of the newspapers of the day was The Evening Star (later The Washington Star). Might have made things uncomfortable for the folks at The Washington Post, the team and a competitor sharing the same moniker.

But it’s a moot point. The whole deal - despite Post headlines on May, 28 1973 proclaiming “Baseball’s Back!” and that the Padres would play in D.C. in 1974 - went south. City leaders in San Diego threatened a $72 million lawsuit, support from Major League Baseball for the sale/move quickly eroded and the Padres stayed put. RFK Stadium remained devoid of baseball - save for the occasional old-timer’s game or major league exhibition - until 2005.

But what became of the gray-and-red jersey modeled by Freisleben four decades ago? Were they ever mass-produced, or was the then-Padres’ pitcher’s attire a one-off? If one was made and modeled, surely there have to be others, right? Is the historic jersey in storage in Kansas City, Mo., where Freisleben is believed to be living? Is it shoved at the back of a closet somewhere in San Diego? Does Nats owner Mark Lerner dress in one, putting his Nationals uni over it on those chilly days when he shags flies before games? Is there one tucked away in Cooperstown, N.Y., at the National Baseball Hall of Fame and Museum?

It’s one of those great baseball mysteries - like the exact dimensions of the strike zone and what constitutes a balk - that may never be known.