I don't think they were ever intended to be an exclusive for any one distributor. Davidson's just happened to purchase all Ruger had when it showed up on Ruger's inventory list.
As I recall, there were something like 60 made.
I think somebody at the factory erred in chambering chrome moly cylinders in the .327 round. So to get rid of the stock, Ruger just went ahead and shipped them out.
Ruger 45..be sure to pass the serial number on to me so I can see if it falls within the known serial number range for this model. You can send me a PM.
Thanks!!
Chet15