My limited interest in this add waned when I saw the sellers “phone number”. Any one spelling one or more of the numbers (don’t even get me started on the “ate” as opposed to the “eight”) always raises suspicion. Primarily because when the actual number is provided it can easily be searched for validity and / or fake or fraudulent post(s) in the past. Jumbling up the phone number with words typically means there is something to hide so it can’t be verified...not to make it “bot proof”.
One more thing: the VAST majority of items listed for sale on this site have at least one picture. Unless I missed something I have yet to see any evidence this 1957 piece of glass in a 1980’s box actually exists.
The majority of us are not detectives as you stated. We are, however, skeptical when an add such as yours contains multiples clues leading one to believe it is fraudulent. Couple those clues with the overwhelming defensiveness you presented in several posts and it only raises more suspicion.
In hopes of ending this on a positive note: good luck with the sale.