jimmuller 

That looks like an early 70's UO-8, a much smaller version of my own '72. They ride nicely, especially with alloy wheels and crank, pretty quick but not twitchy. You just think where you want it to go, give it a tiny encouragement, and it goes. They handle rough roads very well. The 28lbs weight would have been fully assembled with steel crank and wheels. As for the tubing, others can probably answer more accurately but Peugeot always labeled them as built with special lightweight tubing, in other words, their own and they ain't saying. The frame weight itself wasn't especially high though. My 531-tubed Raleigh weighs only 4 lbs less but that's with alloy parts.

Someone here described it as entry-level. That's not quite true. The AO-8 was entry level, with a cheaper crank and wheels, no chrome on the fork, and solid axles in low-flange hubs. The UO-8 had Rigida Cro-lux rims (mine are still shiny bright), Normandy high-flange hubs with Atom quick-release skewers, a nicer Nervar crank (still steel though), and the chromed fork. Probably a better saddle too though I don't remember that.

That one still has the seatpost collar; unless you are doing a restoration you can remove it and use a "normal" French seatpost. The original brakes would have been Mafac Racer centerpulls which would stop a freight train. Be aware that the rear dropout spacing is 120mm.

I wouldn't recommend painting it unless there is a serious problem. That original paint and decals are distinctive. As they say in C&V, it is original only once.

One more thing to consider. It should have had a brake cable hanger on the seat post bolt. If you use a sidepull on the rear that won't matter but if you go with centerpulls you'll need to rig something.