Here's my Medical
ID necklace, next to a quarter:
I got mine from www.americanmedical-id.com,
they sell Medical ID Jewelry starting at $21.95 -- and can be reached at
800-363-5985. I'm sure there are other places you can get them, too.
I got the 24" stainless steel necklace -- reasonably priced, and comfortable
(easy to get on over my head).