Tires are 622-40 (700c). The hardware all seems to be standard metric bits. Other than both pedals, I haven't taken anything apart but I found a few posts online about the Kharkov headsets being a non-standard size and replacements are nearly impossible to come by. The bottom brackets on these might be an odd size too.

No fancy, ornate lugwork on this one!

Note the little factory stamp on the inside of the chainwheel. I found the same markings on the chain.