I believe it is from an Ampex PR-10-1. This machine came in a mono, stereo and 4 track version. The electronics are from an Ampex 354 with a different faceplate:
I have two PR-10's (stereo model) and it looks very much like them, as said above. NOT a service-friendly machine in my opinion. The output cap was dryed out on all channels so none passed much audio, and also the trimmers under the lid had to be replaced on one of them... Custom part (all four trimmers in one package IIRC :). Found some small Alps pots to replace it. Very hard to reach without breaking the stiff cabling running all over the place. Anyway, I hope you find what you're looking for!