That Davidsons Supply Co. was the precursor of the now Davidsons (Gallery of Guns, etc.) located in AZ. https://www.davidsonsinc.com
From their site:
In 1932 Davidson’s opened its doors as a wholesaler of used auto parts in Greensboro, NC and over the long history of the company it also supplied general hunting and fishing supplies, consumer electronics, special liquidation purchases, and general sporting goods. In the 1980’s, Davidson’s shifted its focus to rest squarely on the wholesale distribution of firearms in the U.S. and today is one of the country’s largest firearms wholesalers. We believe our success depends on having a progressive mindset without sacrificing the traditional values of excellent service. Davidson’s brings you the best of old and new; years of experience, a huge firearms inventory, innovative services and a rock solid reputation in the firearms industry.
Being cataloged as a SS-32P, that it could an overrun of a French contract (Manurhin) but it could also be one of those shipped to a US law enforcement agency under contract. Davidsons should be able to help you out. Let us know what you find out.