I have an complete unrestored Bottecchia frame probably older than yours - it may give some clues as to decals and finishing. As near as I've determined, mine is late 50's, non-US imported (no Carnelli anywhere), but still full chrome under paint and a very similar seat lug. Do you have a full suite of pictures anywhere (I am new on this forum).

I'm at work, but can post some photos of mine this weekend. Cheers!