Grabbed three new ones (to me) for my Mantle PSA collection at the Small Traditions auction last night. Put in some bids before going to bed and they held up. Bid on about 7 other auctions that weren't highest, but mostly 2nd place.
Seems like the 1960 Nu-Cards are much rarer than the 1961s, but they didn't cost much.
1960 #22 PSA POP of 72. 1961 #422 POP of 308.
1960 #50 POP of 60. 1961 #450 POP of 284. For $80 for both including BP, not too shabby. And SmallTraditions shipping/insurance was very reasonable.