I would check on localbitcoins. I have had more success with % per Amazon card there than on here. I do recommend SSS_SS1 if they are still buying them. I have had 3 successful trades with them in the past month. I think their rep is over 1k as well.
Whoah, localbitcoins added amazon and steam cards! That's quite awesome! Now that purse.io doesn't sell giftcards anymore it's good to have more options. Too bad there are not many traders accepting or selling EUR amazon cards.
@OP I would definitely recommend localbitcoins! Just make sure you pick someone trusted, that's more important than picking someone that offers an overly attractive price.