Hi,
I also have a handful of old manual focus lenses. All of them are seldom in use but they were rather cheap, except for my Arsat 55mm f4.5 shift lens (cost me with EOS tilt adaptor more than 500Euro). I can recommend the M42 lenses. There are lots of them. The adaptors are readily available and cheap. The autofocus confirm chips don't work that well for me... but you can give them a try.
For 135mm I can recommend the Auto Vivitar Telephoto 135mm f2.8. The manual focus works very smooth, the bokeh is OK and focus to infinity works (albeit a bit soft). The Carl Zeiss Jena (CZJ) 135mm f3.5 is also OK. I have the Prakticar version with PB mount, which is identical to CZJ M42 except for the different mount. Like the Vivitar it's all metal but a bit small and light weight.
The old CZJ lenses are often a bit more expensive than the other M42 lenses, at least here in Europe. This has more to do with the name with the quality of the lens. The above mentioned lenses are at least equal and I actually prefer the Vivitar, which is better build.
BTW, be aware that the adapts work different on full format and crop bodies. The PB mount works great on crop but on ff the lens' end hits the mirror. I had to manually modify the original lens mount to fit it onto my 5DII. Now it works without a problem.
Be aware that some of the decades old lenses produce a slight yellow color cast, which comes from the ancient lens coating. Some used a weak radioactive coating and with its decay, the yellow color cast develops. The coating is the weakest point of these lold lenses. My Arsat is very sturdy build, has great resolution and is reasonable sharp but the coating is terrible, although it is just a 12 years old Ukrainian medium format lens. But try to show me any affordable 50mm or 55mm shift lens...
