$50 + shipping seems high.
I bought mine for $41.56 brand new from an online dealer, and that was the shipped price. I got the part numbers from a previous thread (http://www.v6performance.net/forums/showthread.php?t=26982
Post #13, I did not buy the extra endlinks and bolts and nuts he mentioned)
Prices at the time I bought mine from www.hondacuraworld.com
20mm rear sway bar - part# 52300-SEP-A11 $31.42
bushings for sway bar (need 2) - 52306-SEP-A11 $ 1.43 ea
bracket for sway bar (need 2) - 52308-S3M-A00 $ .83 ea