Will these BBS RS-GT's fit on an 03 S?
 

http://cgi.ebay.com/ebaymotors/BBS-RS-GT-FORGED-WHEEL-SET-Porsche-997-19-GLOSS-BLACK_W0QQcmdZViewItemQQhashZitem19b785c2caQQitemZ 110453179082QQptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAc cessories#ht_500wt_1158

No affiliation with the seller, but wondering if these would fit on an 03 Boxster S?
Would spacers be needed? I would prefer not using spacers if possible.

I believe the rear on the 19" RS-GT is a 19x11 and I have yet to hear of anyone who has been able to fit an 11' wide wheel on a Boxster without modification of the fender well.

Hopefully someone else with either confirm this or tell me that I am wrong

If one is to presume that the rear wheel is in fact 11 inches wide ( because the listing does not clearly state is), then no way, no how will a 986 Boxster accommodate a wheel of that width. Besides, for 4K plus there are far better wheel choices out there that will provide you with perfect a fitment in terms of sizes and offsets.

Holy crap! Look at the second image, don't know if it's a photographic anomoly but the inside of the rim looks possibly bent. If I were tossing north of four k on used wheels I'd like an certification from a tire shop that each one spins true.