I can't help ID the machine either.
However, it looks a lot like a very old production horizontal milling machine, converted to surface grinder.
The reason I'm concluding this is that I'm in the process of doing just that. I have a Whitney No2 horizontal production mill that I got for that purpose. Like the one in this photos.
It has - like yours - a rack and pinion lever operated x axis, a screw driven Y and z axis. Mine also has a counter-weighted vertical movement of the spindle carrier (unlike yours) which I intend to modify to very fine drive.
I may of course be way off the mark....