Hi Terry,
I had bad vibes (hahahaha) from POLY T-C bushings in my Mustang, so I replaced them with rubber and went with rubber in the Z.
I can't recall the brand (Beck / Arnley perhaps) I bought "Stock" rubber bushings from Black Dragon, about 5 years ago. They were exactly the same size as the 25+ year old originals.
Their current prices are $30 for rubber, ($35 for poly.)
PartsAmerica (local to me Advance Auto parts) lists 3 manufacturers, no MOOG:
Beck / Arnley pn#1013850 $3.44 ea.
TRW pn#HB1175 $3.88 ea.
McQuay - Norris pn#FA1317 $8.99 set of 4.
Rubber set is $20-$25 on EBAY:
http://cgi.ebay.com/ebaymotors/Datsun-240z-260z-280z-Front-Tension-Rod-Bushings-NEW_W0QQitemZ220204852802QQihZ012QQcategoryZ6763QQssPageNameZWDVWQQrdZ1QQcmdZViewItem