Did you find a keychain you like yet?
I found this on ebay:
YORKSHIRE TERRIER 1982 Rawcliffe PEWTER KEYCHAIN - eBay (item 320141820479 end time Oct-19-08 07:46:16 PDT)
I also have a bunch of these that i bought for the GE's.
Pewter Yorkshire Terrier Dog Key Chain ~ Great Gift - eBay (item 130003175521 end time Oct-18-08 05:54:48 PDT)
These are pewter and heavy and made really well. I love the little paw print charm too.
i just put in yorkie pewter in the search...there are a bunch of cute items there. Good luck!!