Hi Michael,
I have just checked the inscription of my 707 and it says "Boeing Intercontinental Jet", so there seem to be different letterings around.
Your remarks about the Award Verkuyl 727 are correct. There are three colours existing, copper, silver and gold. As far as I know, Verkuyl used two moulds, one with a detailed third engine and one with an easier engine, where the intake hole is missing. I have the copper one with detailed engine, enough for me....
I am not sure about different colours for the Lutz+Weiss DC-10 (maybe..), but the A300 for sure not. Just silver there, maybe with different mileages printed on the stand.
The TCO 727 and 720 have indeed the same body and wings, comparable to the original ones. Boeing used same segments for the manufacturing of the 707/727/737 fuselages (wings were different). And what makes the originals less expensive, is also valid for the tin toy planes..
Regarding the age: I have no solid sources, but TCO stopped the manufacturing of the CV-340 and the Connie in 1968, so these newer models should have replaced them more or less, production maybe lasted until 1973 or so...
Greetings to Stuttgart!
Chris