Saw this on ebay thinking it was a early 500
But lo and behold it is a 5302!
http://www.ebay.com/itm/151912783758 (http://www.ebay.com/itm/151912783758)
It might need a ringer. Fold a Phone refurbs did not always have ringers.Were sold before it was legal to install your own telephones.Sometimes had a buzzer made from a SC ringer coil and a metal strap