You may know this, but FYI just in case, early 753 was metric sized, 28.0 and 26.0 mm in the main triangle instead of 28.6 / 25.4. Chainstays 22.0 instead of 22.2. Most any 753 frame made by Jim Merz for example, or a Raleigh Pro made prior to the SBDU.

So if you need a tube or two for a crash repair (common scenario for why someone is looking), you might be looking for a metric tube, depending on what fits the existing lug sockets.

I have a couple sets of metric 753 (and metric lugs and BB shell) but not for sale, sorry, hoarding for making into frames, hopefully before I die. (I assume it's harder to build them after death, but who knows, maybe easier in that Big Frame Shop in the Sky?)

The last few sets I saw for sale sold for a silly amount of money. It's really not that great, so other than nostalgia, there's no reason to pay that much. Make it out of Prestige and put 753 decals on it, no one would know. No, I would never do that! If only because I never used any tube decals. Other than the occasional "Guaranteed NOT Built With Reynolds 531", usually put on a Ti or alu frame, super funny on a cabron frame.