[kf4rca]

This is as close to it as I can come. Its from the 50's. The octal socket is for a crystal oven.
There are 2 books of schematics covering Pre-Progress but I only have Vol. 1.
Low band (30-50 Mhz) radios were made in three splits. Thats what the suffix numbers indicate.
The reason there is virtually nothing on the web is that these became obsolete long before the internet came about.
I'd hold on to it till the next hamfest and maybe you can sell it for $20 to a ham whose building a 6 meter repeater. The tube type equipment holds up much better compared to solid state when hit by lightning!