That link to the Vivitar manufacturing codes vis a vis their serial numbers is one I had stumbled upon a year or so ago, and I found it pretty handy
Vivitar 70-210 Series 1 Macro Zoom Lenses - Mark Roberts Photography
to find out when and by what company a couple of Vivitars I own were made.
Vivitar released a 55mm f/2.8 Series 1 1:1 macro lens in the 1970's, and it's a very nicely-built lens with an incredibly long,precise focusing throw,all the way to 1:1, with a very complete magnification ratio and distance scale. It's a pretty good lens optically, but the mechanics of it are really impressive and what makes it kind of a neat lens. There was also a 90mm macro in the Series 1, built pretty much the same way,with the long, slow helicoid focusing system and impressively complete magny and distance scales, all engraved and filled with colored paint, not just painted on. Both were fairly expensive for their era, with the 55/2.8 retailing for around $340 in the late 70's, which made them more-costly than most first-party macro lenses of that time.
Ah, those were the days...and thanks to these new 4/3 system cameras, a lot of these old lenses have been given new potential uses. I think the Leica R lenses will probably find most of their use adapted off-brand to various Olympus and Panasonic bodies, as well as to Canon d-slr's. Leica's currently without an R-mount body, but I have heard rumors that they are readying a digital camera that can use R-mount lenses (not sure if it's true or not).