Ouch, I recently picked up 4x Topy Wheels (72 date stamped) for my 72 240z. Took them months to arrive, but finally got them on Friday, as I left work early to go collect them I was wondering if it was all worth the effort chasing down these parts and taking time out to go get them. But like you a result like this indicates it is worth it.
My first 240z cost me $3,250 in 1998, and it was original with steel wheels and caps! I didn't keep either :(... instead I put 260z alloys on it.
So glad I collected 'D' caps and AM Radio's a few years ago too!