p.2 #2 · leica r summicron 35mm f2 vs zeiss 35mm zf.2 (and 50mm f1.4 zf.2)
I got my Summicron-R lenses from www.ebay.de It seems that many European sellers, especially at a local level, do not accept PayPal (bank transfers in Euro-zone seem to be preferred) As a result you may not find many interesting listings in international sellers search. No problem; I conducted my purchases of mint Summicron-R lenses using Google Translate as a reply to original bids. Once you initiate a contact the rest of transaction will be conducted in English. IMO, Europeans keep their photo gear in much better shape, so it's worth to try checking among sellers barring their glass along toys used Nina Hagen, Milli Vanilli and Boney M. records.
p.2 #3 · leica r summicron 35mm f2 vs zeiss 35mm zf.2 (and 50mm f1.4 zf.2)
There is no difference optically or mechanically between German an Canadian Leica lenses. The only difference is to a collector of Leica gear. It is time to put the myth to bed.
It has been tried many times.