I hate to be the bearer of bad news, but you folks must not follow any of the big auctions. 1968-1972 Novas, especially big blocks, have been hot for the last couple of years. Here are some examples from Mecum:
1970 SS, 350 4-speed, sold for $39,600 at Kansas City on Dec. 6th
https://www.mecum.com/lots/KD1219-40...rolet-nova-ss/
1970 SS, 396 4-speed, bid to $35,000 but did not make reserve at Kansas City on Dec. 6th
https://www.mecum.com/lots/KD1219-39...rolet-nova-ss/
1969 SS, 396 4-speed, sold for $44,000 at Las Vegas on Oct. 11th
https://www.mecum.com/lots/LN1019-38...rolet-nova-ss/
These are just a few – matching numbers 396/375 Novas that are what you’re calling ‘concours’ regularly sell for $60k+. I’ve been in the Nova game since ’66 and have owned several, including the matching numbers ’66 L79 that I still have. The days of picking up a nice hi-po Nova for cheap are long gone.