Over the last year or so I have gotten a whole bunch of packages of Yankee cards from various bloggers. As a result I have more dupes of Yankee cards than any other team by far. If anyone out there has some specific Yankee needs or just want to do a Yankees-for-Yankees (or Yankees-for something else, I'm a pretty omnivorous collector), let me know!
My most recent package was an 800-count box from GCRL, about half of which were dupes. Many are from the late 90s and early 00s. For example there were two unopened packages of a 13-card Collectors Choice Yankees Team set from 1997. I opened one for myself but have the other unopened for a trade if anyone is interested.