I recently sold a 1957 Cardinals Jays Publishing team set, including that Musial pose for $93. Link:
http://www.ebay.com/itm/1957-Jays-Pu...gAAOSw5cRZFz42
The seller of the individual Musial got a good price, there were 3 buyers who bid over $175 for it. There are many Musial collectors who pay well for difficult to find pieces. Here is another example of one I sold recently:
http://www.ebay.com/itm/1953-St-Loui...cAAOSwsXFZF120