I saw this posted a while back, and have yet to look into it. Someone asked about the very same thing and the response was check out indy etching.http://www.indymetaletching.com/
Looks like laser engraving and 3D printing is a little different. At the local maker store, they use a acetone "vapor" to smooth out the parts finish after it's cooled. The acetone seems to smooth out the rough lines and gives the part a little more shine.Not sure if this can be done with your parts.
Rich, your bands van would make a great dio, hope that year of van is available, as it would be cool to see.