Yeah the Cousy's are a nice collection centerpiece
The Berk Ross story is as follows. Berk Ross produced cards for a three year period or so to rival bowmans card releases at the time. Bowman only had the one year to date with 1948 but ruled the roost with its baseball product.
Berk Ross mad a few sets in 1950, 51 and 52. With only the 51 year with Basketball. They were perforated in two card panels are attatched ones are like hens teeth! A Cousy like that would fetch $20,000US + in EX condition.
Berk Ross only lasted about 3 years though before bowing out of the hobby but not before making some of the most valuabe baseball cards of all time though. Ruth, Williams, Gehrig etc.
Here is a Bill Sharman attatched that is not mine.
Only two well known players are in the set of Basketball of four players. The Cousy and Sharman. The Sharman is in my sig
Therefore as each player didn't appear in 1948 Bowman its their FIRST appearance on a card and therefore a XRC of sorts. Sharman is in his all star uni and Cousy in his Holly Cross uni.
With the perforation its hard to get a high graded one of course.