I'm looking to the replace the old 4-screw chrome centercaps for the old dealer option slotted mags on the '72 (upper right on pic below). Motorsport has been out of them for quite some time and isn't sure when they will get some in. Does anyone know where else I can find a new set?

Try Massey's in Oklahoma, they seem to have lots of obsolete center caps. I got a set from them recently too.

http://classiczcars.com/forums/showpost.php?p=191337&postcount=16

Email this ebay seller. http://cgi.ebay.com/ebaymotors/Caps-ET-Slot-Mag-Empi-Ansen-American-Racing-Datsun_W0QQcmdZViewItemQQcategoryZ43961QQitemZ120071638983

He has several different cap logos available. I got a set of US mag logos and a set of blank ones that I used the MSA Z logos on. The blank ones are less, about $25 I think.

-Mike