The only tag there is what I said above. Yeah I agree with the missing piecesX2...K2 Z50...built in later 1970 and 71.
There SHOULD be a vin tag riveted to the front most part of the frame...steering tube.
$800 isn't ridiculous right now...but 5-600 sounds a lot better for that bike. It's missing a lot of very expensive parts.
Yes they were but should still have a vin plate on the front of frame…look close and you should see 2 very small holes were the rivets spiral in to holes to retain the vin plate.. along with sticky adhesive on back side of vin plate.Isn't the VIN stamped on the (chain side) rear axle - wheel mounting plate?