WELLLLL,
AFTER some weeks of idling and taking car of more important stuff, I finally got on to it!
The problem was to find some screws (four of them) that can be used to hold the bellows to the front standard, since the camera didn't come with any.
The lens is held by a regular retaining ring, which I have on my copal 0 shutter.
In my search for those screws, I remembered that I had a Yashica Electro somewhere, that was flooded or exposed to sever moisture in someone's attic
or cellar, and I was given it for nothing.
So I started digging into it with my screwdiver, removing every screw I could come by, hoping that I'll find four that would be an exact match. Using my caliper, I measured that there are about 4-5 varieties of screws in Yashica, from 1.3mm to 1.8mm thread, and various lengths, and various head shapes.
I learned that the original ones that hold the bellows to the front standard were 1.7mm thisck and about 3mm long, but when tried this size, I couldn't screw them in, so I tried smaller sizes and about 1.4 to 1.5mm thread size seemed to fit.