Does yours from the 70s have the big O in CO, vadava? If so, does it also have a hollow ink Zildjian on the bottom? Any model ink on the top? Note that there seem to be big CO vs Co, 3 dots and not, dots in U.S.A vs USA. There may be other variants as well.
Yes it does, CO and hollow ink on the bottom. U.S.A. is dotted like so. No ink on top. The 3 dots are not there I think, but I actually find that bit confusing. In the stamps where the 3 dots are absent in the arabic writing, there are two dots and two lines in their place, correct? I have the latter, so not really 3 dots (more like this .. _ _). Could it be from the 80s maybe?