I can't disagree agree with scatter cat, as it may be worth more of your time to get something a whole lot closer to usable.
But if just as a hobby project, it could be fulfilling to make it something useful. It will be a long project I expect though. It kind of depends on your mindset on what you'd like to do.
Most here would recommend 3 phase over single phase, as a short answer.
For parts I expect you will need to make or modify. Used for that age bracket will be few and far between.
Its been rained on for a while, so hard to hurt it now. For the ways, I'd soak them with wd 40. And use 400 grit emery cloth or sandpaper. Soak both the sandpaper and ways in wd 40, and start going over it. Use rags to wipe it dry and start over.
Its not what I'd want to do with freshly ground and scraped parts, but all the muscle you put into it by hand will not approach .0001". Just don't use power tools on ways.
For the x axis screw. You want the tpi to equal the graduation marks of the handwheel dial, so that the math is right for one 360 degree revolution of handwheel/dial/screw .
Assuming you don't have those, might try converting a screw, dial and handwheel from a bridgeport, or the like. with similar table length. Bridgeport parts are reasonable and available. Won't be bolt on ready. But a little modification could probably make it happen. Just an idea, might have a look at the parts to see how doable. Where and how to attach the feed nut for screw to move the table, getting that nut in middle of screw with table centered on machine for even travel, etc.
As an example a Bridgeport x axis screw has 5 threads per inch, the dial has two hundred .001" increments for one rotation. The reading on dial starts at 0, and is .200" back to that 0.
5 full rotations equal one inch.
5 x .200" = 1".
One question I'd have though, is what feed does that driveshaft on the side drive ? And how does it work ? Might need to lift the table and look at that.
And before you start investing, go over the rest of machine. Are gears intact, or teeth blown off etc.