Auction for basketball ?
 

Any thoughts on best auction house(s) for mid 70's high graded basketball. ?

SCP Auctions for sure !!!

Rea
 

REA gets good prices and has excellent service.

David Kohler has an outstanding collection of early basketball cards and premiums and is very knowledgeable about them, so if you have oddball stuff, that's definitely where I would go. For what the OP describes, any of the reputable AHs would be fine, just depends on their strategy for lotting more than anything else.

We've done quite well with vintage Basketball. You can search through all our previous auctions, no need to sign up. Have Chamberlain, West, Alcindor and Erving rookies all PSA 7 or better coming up in September.

Auction prices are all about which sites get the most traffic and what their fees are. You can compare all website traffic for each of the major auction houses using a web search tool like Alexa rankings. I would look each site up and see who gets the most views if I were you.

If you're selling a marquee card, sure, the big AHs are interchangeable. If not, then it is also about niches and placement. Some AHs are better known for specific things. Look at what the AH has sold in the past and how they've handled it. Huggins & Scott, for example, has sold some very big basketball. How the AH sells is critical. If your stuff is going to be lumped together into a big, haphazard single lot to make some AH-mandated minimum estimate, all you are doing is packaging a wholesale lot for someone who will bust it up and sell it on eBay. Might as well do that yourself.