I owned a machine shop until two years ago and worked with used equipment dealers often. Old forktrucks are a dime a dozen with these guys. I worked with a guy in Columbus that dealt specifically with gas & electric units. Let me know if you want to try that approach & I'll email you the info. If there is such a thing a a forklift graveyard this would be the place to start.
I have a 1971 TOWMOTOR forklift that I need a motor for. I am not sure what motor is in it as it was in a basket when I got it. I have some casting numbers. You mentioned a junkyard for forklifts ... I would like more information on that if you have it.