I also have several extremely old gift caps available for trade at:
http://www.neopets.com/~metbo
Items valued for 1-2 GBCs.
I will trade these 1:1 for something of similar value, or 2:1 for GBCs.
All buyables are 2:1, 3:1, 4:1, or 5:1 depending on how many boxes I get in the cap.
Boxes: Yes
Numbers in this section are rough values according to /~korolie.
Since the re-release, who knows, I might find a trade for some of these? Actively seeking anything with a 99.
These are items I need to complete sets, superpacks, mmes, etc. Mostly here for my own reference.
I would be happy to trade for any of these items, but I'm not in a rush. However, if you have one (or more) and are interested in anything above, please let me know!