When my son reported in June 2011 he brought his "Certification of Birth" certificate from Pennsylvania and his original SS card. We also gave him color copies. I am almost positive we got the original SS card back and the "Certification of Birth". I would send the originals of both with copies and tell your son to give them the copies unless they insist on originals. I seem to recall that was my advice to my son.
Worse case scenario.....are they not going to in-process you son if he only has copies? I doubt it. I think you'd probably get a call from him asking that you get a certified copy and ship it ASAP. If you don't currently have the originals you might want to order them now "just in case". JMPO....
Good Luck to your son and congratulations!