COOPERSTOWN, N.Y. — They stretch across the front row of a display case at the official Hall of Fame gift shop, autographed baseballs in plastic boxes from the five living players to be inducted on Sunday. Edgar Martinez’s ball goes for $249, Mike Mussina’s for $199 and Harold Baines’s and Lee Smith’s for $149 each.

A baseball signed by Mariano Rivera costs $699, nearly as much as the other four combined. Then again, you get what you pay for: in Rivera’s case, an elegant autograph, each letter scripted with the precision of a final pitch of a World Series.

“Many times, I threw the pitch and the results were to my favor, so right after that, I don’t have to throw no more pitches,” Rivera said last week. “I was happy with that — and then I had to make sure that I don’t end up in the bottom of the pile.”

Rivera threw his final pitch in 2013, and now he is on top of the pile: the only Hall of Famer ever elected unanimously by the baseball writers.