The advice to not tear down is misguided, especially for a machine that hasn't been used in quite a while and has dried oil all over it. South Bend's 10L and 10R lathes use a wicking system to get oil to where it is needed. If your wicks are caked/clogged up with dried oil, your machine could be oil starved and rapidly damaged by use. Unfortunately, the only way to get to these wicks is to tear the machine down.
I bought all four oils from Enco, now MSC, so you should still be able to get the gallon jugs from them. Also try McMaster.
Perhaps your post was in response to mine, dunno, but we may be interpreting the terms "rebuild" and "teardown" differently.
"Rebuild" to me means remanufacture: complete disassembly, rescraping and realignment of all ways, replacement and remachining of all parts in less than excellent to perfect condition and a complete paint job. And "teardown" means complete disassembly.
Which is why I advised against it.... But perhaps you mean something else.
I agree, difficult to turn handcranks need to be fixed and spindle bearings should have oil. The lathe should be gone over with a finetooth comb and the oiling diagram consulted to make sure that each and every oiled surface is getting oil. And anything else the OP thinks should absolutely be fixed. But rebuild? No, because this lathe just isn't worth the time, even for a homeshop. Check the Monarch forum for examples worth a rebuild, but this lathe ain't never been a Monarch (or even a heavy ten) and never will be. I'm speaking in economic terms here and counting the OP's time as worth something.
I'm definitely not in favor of a novice rebuilding the machine to the degree you explained. I mentioned "teardown", because that's what you have to do to get access to many of the wicks. I agree that most South Bend lathes are simply not worth the effort to rebuild them. But some people will take the effort to rebuild a '66 Volkswagon Beetle. To me, a VW bug isn't worth the value of the scrap metal.
As a friend of mine used to say - 'words are weapons, choose them carefully'.
And what one person sees as an effort worth doing another does not. Good thing we don't all think exactly alike, I would see it as pretty boring.
I bought a 1945 Heavy 10 'War Baby' in similar condition to the OP. Not much usage at all but had been 'preserved' once with heavy lathering of grease/cosmoline then later stored in a school bus garage for 40 years or so. About as filthy as anything I have ever tackled. but under the grunge even the original decal on the apron top was somewhat readable. Not my first rodeo, but I tore it down to every piece that could come apart, totally clean, replace all felts then reassemble and adjust everything. Definitely not a rebuild but what I classify as a refurbishment. In this case I even painted it just because I wanted to. So now I have what is to me a decent lathe for home use - and that I have been using to teach my grandson how to use as he is interested. I figured it needed the total bath just to keep the crud from wearing the soft bed, etc.
Was worth it to me - even posted on here what it looked like before and after. Your mileage might vary and I might be nuts. But the lathe ran pretty nice Saturday when I needed to do a little work with it.