I didn't miss the Dempsey...
The boxers are Sullivan, Jeffries, Dempsey, Gibbons (all 1955 inductees) and Baer (1959 inductee).
Prices were all over the place, from about $12 on a few under-the-radar sales up to $150. Conditions were varied as well.
Here is a link to the FOE web site listing of their sports HOF. As you can see, the known cards all date to the 1955 and 1959 inductees, which nails the issue date as far as I am concerned since you can't issue what doesn't exist and this HOF didn't exist in the 1940s. I haven't seen a Thorpe...yet:
http://www.foe.com/about-us/sportshof.aspx