Depends where you bought them from. I has a similar problem with some bought from Choicestationery and they were good enough to do a part exchange swap with some for my new printer. Obviously only unopened and with plenty of shelflife left but worth a try.
I don't use Ebay myself, but I've been reminded my Father-In-Law has an account so I might ask him to see what he can do for me. I've also asked a friend from work to put the feelers out for me, as he knows quite a few people with Epsons apparently.
Ten of the cartridges are from Choice Stationery, so I could try your suggestion as well BT. I assume I just email them with the query.