Pricey Underwood M1 carbine...is this legit??

[Bruce McAskill]

Only one problem Jim. The type 3 barrel band didn't come about until about the November 1944 time frame. If it is an E serial number it would have been made well before the type 3 band was available. They were originally experimental models that were later used for presentations. Known numbers go at least up to #259. This one being offered is about as wrong as can be. As is it's maybe $850 carbine the same as any rebuilt. The only rare thing is what is in the sellers mind.

[Sunray]

Dealers on auction sites always embellish their marketing. The guy only sells firearms on GB too.
That's probably a tung oil finish or it's been heavily waxed and polished. The finish on the metal is a long way from being "presentation" grade as well.
"...A bayonet lug on..." Probably put on during the post war rebuild.