The $20 Saint looks like an early, cast medal; this, in comparison to most of those cited by wheezydog on
ebay. Interestingly, there's another early-appearing medal, a
Lincoln Cent. Both that one and the $20 seem to have above average interest for bidders. These may be paperweight medals that were sold at early fairs, expos and tourist spots. While I'm not familiar with these types, I have seen a similar one from the 1915 Pan-Pac Expo. The current, $39 bid suggests it's an early item of interest to some segment of exonumists. There may be a reference book on these by Stephen Alpert. Often, these large medals are marked by the maker, but I see no such signature hereon.
Regarding the "Looks like they are not rare then" observation ... the term "rare" is a relative one. Apparently, at this point in time, someone thinks that this $20 coin medal is worth 13 times the price of similar items. In my fifty years of collecting tokens and medals, I've not before seen this $20 medal. In terms of availability, I'm thus inclined to think it's relatively "rare" them. That said, it's not an item that I'd bid on ... not my cup-o-tea.