The whole tag thing is out of control. I'm seeing shrouds now sold on ebay with the tags missing, then the tag in another auction for big bucks. Saw a tag today for $58 or something. At some point, one has to consider that any bike that came originally with a Tecumseh is never going to be so valuable as to warrant $58 engine serial number tags on period correct, or pseudo-period correct engines.
I have "never" had anyone crouch down low, grab their reading glasses, then look up at me with a gleam in their eye and say, "Dave, there is no way that 1972 HS40 was on that 1970 Cat."
Of course I haven't actually met the people from here who WOULD do that yet, LOL but at $58 I will take my chances and bullshit everyone when I am talking about a $400 bike.