Well, I think you could get 600 if you do a limit of say 5-15 copy's. If I can get $1100.00 for a casting I am pretty sure you can as well.
Sculpt something out like this one and send it to me. I can make the mold and do the castings for ya, then send them back and you can dress them up each different if you want and see what happens. Offer is always on the table of course.