they have stuff for that as well. IIRC, you wash down the piece really good with soap and water and then spray on this mold release stuff and bake the part in the paint booth for a few minutes and then wash it again and it's ready paint. a good painter will know how it needs to be done. i would suggest calling around and finding out exactly the part is supposed to be painted.
on the other hand, i think there are also fiberglass repro's available too, can't remember where from though.