You have to be a little cautious buying a really old bike. Everything has to be there. The seat leather and tires can be missing but that’s it. If your missing a cog or an axle nut nothing made in the last 75 years or even less will fit. The threads are different. A new headset for a one inch steerer won’t fit. Usually there is a lot of wear in the bearing cups and you have to use them anyway. The pedals threads almost always are the same as now. Modern bottom bracket races, even for a single piece crank, won’t fit the crank threads. Doesn’t matter if it’s Schwinn or not, won’t fit the crank. $1400 is a little steep, but if all threaded bits are all there and it’s all original then it’s probably ok. Parts can‘t be rusted through. I have an old timer with a cracked bb race and can’t find one that threads on. I ride it anyway but the bb is a little loose. It also has some holes rusted through the handle bars on one side. A carbon fiber wrap fixed it. The other side has black tape so it looks balanced. The tolerances are incredibly precise, despite the age. Very likely the nickel plating will be gone and the seat post and seat clamp won’t get tight enough unless you use shims. This is the one with the cracked bb race and rust holes in handle bars.
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