Next door to the newsstand is a small kiosk that sells official Trump-branded merchandise: higher-end offerings, like cuff links and sweaters.

The only claim of authenticity Mr. Sewani makes on his own merchandise – which he buys from the least expensive wholesalers he can find – is that he sells it at “the source.”

“That’s the key,” he said. “People know that if it comes from Trump Tower, it’s genuine.”

And while the kiosk selling the official stuff was quiet on Sunday, customers thronged Mr. Sewani’s store, which he attributed to the bargains he offers, like the more affordable tchotchkes displayed amid deodorants and cold medicines. Above the M&M’s and Twizzlers were some “Comb Trump” fridge magnets ($9.99 each), with shocks of yellow hair. Near the lottery machine were Trump commemorative coins and key chains. Coffee mugs were going for $19.99, and the top sellers, the T-shirts, were $20.

Mr. Sewani said he grew up near Mumbai in a wealthy family. His father was a coal distributor who later invested in real estate. Mr. Sewani studied to be a civil engineer and in the mid-1980s met his wife through a newspaper advertisement seeking suitors for an arranged marriage.

“She got 101 responses and chose me,” he said. They married two weeks after they met and moved to New York City. Mr. Sewani soon invested in a stationery store in a Manhattan commercial building, the first of the two dozen he said he now owns.