Generally speaking, if you are looking to buy anything related to the New York Mets, I’d prefer you visit the Handpicked Mets Store, as a fraction of the sales goes toward the server bills that keeps MetsToday going.
However, I understand that Amazon doesn’t carry everything, and in fact is quite sparse when it comes to really cool stuff, such as Mets collectibles. That said, whenever I find other online stores that offer stuff not available through the Handpicked store, I’ll post it here.
For example, SportsMemorabilia.com has a vast collection of Mets memorabilia — over 800 items, in fact. There are the usual signed balls and bats, but also some neat black and white photos autographed from the heroes of yesteryear, like Cleon Jones, Yogi Berra, Jerry Koosman, Tom Seaver, and others. One of my favorite unique pieces is a photo of Buddy Harrelson and Pete Rose trading blows in their infamous battle during the 1973 NLCS — signed by both players!
A similar “dual autograph” photo is of Mookie Wilson running up the first base line as his grounder goes through Bill Buckner’s legs. There are plenty of esoteric items as well … for example, where else can you find a game ball from Eric Valent’s cycle, signed by Valent?
If you’re looking for a unique gift for the Mets nut in your life, SportsMemorabilia.com is worth a perusal.