Casually looking one might confuse this wall phone with the Western Electric 356, and pay too much. But it isn't.
http://www.ebay.com/itm/361425311382
The phone was properly converted with an electron tube for polarized ringing on a party line, including the proper low-impedance ringer (B3A).
What gives it away is that this phone still has the 101B induction coil and the 354 hookswitch, and an M3 stamp on the housing.
Nevertheless, a nice example of a barn-fresh instrument that was converted undoubtedly by the telephone company in Wisconsin in ca. 1953 or so.