Check out
www.sharkeys.com. They usually have them for sale and they look awesome (I saw them in person last time I was there, they are bigger than you think). I don't see them on their site now but send them an e-mail and ask. They are in Lake Villa.
Another option may be to contact this member "yahutch"
I see her in the Chicago forum and she knows her seahorse stuff. She's in Wonder Lake, IL
I think she has sold seahorses to people before but I'm not sure.
Her Hobby Experience: 5yrs fresh , 3yrs reef
Current Tanks: 135 gal sps/clam tank , 65 gal hex softy/seahorse tank (reidi ) , 75 gal softy/seahorse tank ( erectus ), 35hex seahorse juvie growout, 29g pipefish juvie growout , and sumps ,and refuges , and culture stations , oh my !
Interests: reefkeeping , gardening , and big dogs