JJ in SB Vs Early Raiser

[awless]

Was playing in a SNG STT level 4(of 6) qualifier for a WSOP; the BB was 100(chips), there were 8 players at the table most havin about 700 to 2000 chips. I was the SB and had 1125 chips with 50 chip SB already in. It was a tight aggressive table and they all knew their onions, The man under the gun put in a raise of 325 leaving him with about 750 chips and everyone folded round to me(SB) I was holding JJ but obviously feared he AA,KK,QQ or at best Ak or AQ.

All things considered what was my best play here?

I decided to fold in the end, as I was out of position and didnt want to face either a higher pair or at best a 50/50 crap shoot. Was I wrong?