I posted this earlier as a complete bike, and didn't get any solid leads on what I have. I did get a very helpful suggestion on using acetone to get the rattle can paint off, so I played around with that, and discovered what looks to be the bikes original paint scheme, although there are no decals or labels that might offer any clues.
There is a coat of grey primer under the white paint, and in some areas, it's absolutely impenetrable. In others, it came right off. I was able to remove enough of it to see what looks like a very nice gold paint underneat. I suspect it's the original color. There are three bands of white paint around the seat tube, separated by (guessing) bare metal that was painted with some sort of clear paint. It's shiny, but does not look like chrome.
I went as far as time, patience, and my supply of acetone allowed. I will give it a little more time with acetone, especially around the lugs. Unless I discover something startling, I'll eventually strip the whole thing. I just want to go at it slowly 'just in case', although I doubt I'll be able to get the grey primer off without destroying whatever's underneath it.
I've disassembled the bike down to the frame, and took a few shots of possible spotting features that might help identify the manufacturer. The seat stays are (to me) unusual, and the lugs are somewhat distinctive.
Any help will really be appreciated.