I read an article a very long time ago about using bondo to make a die to stamp a name in flat sheet metal for a tailgate. I think they first cut the letters out of wood and attached them to the bottom of a wooden tray. I can't remember how they made the bondo not stick to the wood. Maybe paint the wood then wax. After they filled the tray with like 3" of bond,hardened they removed all the wood. They made the other side of the die the same way. They used a shop press with plates sandwiching the bondo dies. It did a pretty good job. Smaller pieces with very little draw shouldn't be too hard.
as for companies no help, btt