I bought door seals from JC Whitney. Paid $60 for enough to do both doors. It required some mitre cutting and rubber adhesive, and MAYBE it doesn't fit perfectly, but it cost 1/4 what Mr. Fiat was asking and honestly, for my beater it's good enough.
Bottom line - shop around for close-enough profiles. They're out there and there are plenty of vendors willing to help. Just get the dimensions as close as possible and don't worry about it!