The perpetual is late 80's. It's original. The ones with the 2000 calander are post Sovjet. The logo on the big0 is a Sovjet quality mark. See Raketa leafelet 1989. I don't know what movement is original in the big0 the 2609N or the NANow that I pay much closer attention, I do see that the calendar is of the 80s. I once saw a model that had a calendar for 2000, I believe. I am hesitant in getting this one because of the pitting on the case back. I still dont own a Raketa and so I am afraid the corrosion will get worst.
On the Big Zero, I saw in the Raketa web page from their 1998 catalog archives an example that does have cyrillic and CCCP but no logo like the one above. That is where I am confused with the dials. I see that Big Zeros have a flat crystal and have a beveled case front along with indices markers. I am learning a little at a time.