Of those you mentioned, the XD-11, OM-2 and Pentax ME Super are good choices.
I have experience of most all the cameras mentioned here as I acquired them for purposes of my own research into SLR's dating back to 1957 beginning with the original Asahi Pentax. Here are most of what I have in 35mm showing their relative size differences. I would suggest making sure that the camera you get is fully functional or solid money back guarantee - a very important consideration due to their age.
I would suggest that you consider the age of these cameras. One reason is batteries used. Prior to 1972, most cameras used the discontinued mercury batteries. There are easy workarounds if you really want a camera designed with it. Another is that the older cameras tended to be larger and weigh more then their newer models. In this case they happen to have different lens mounts too.
One camera not mentioned here but worth additional consideration is the Ricoh XR-7 but I do't know the availability of it in your area. Here's an ad for it that outlines it's key features.
The XR-7 is very similar in size to the Pentax ME Super but has conventional controls - as opposed to the push button shutter speed control of the latter. However, it will not function at all when batteries die.
BTW, with very few exceptions, cameras with automatic aperture capabilities may offer 1 shutter speed (sync speed) when batteries die. The exceptions are Nikon FM3A, Canon New F-1 and Pentax LX. The FM3A has all shutter speeds available while the other two only have sync to top shutter speeds available.
I'm into night photography and make extra long exposures that usually last tens of minutes in duration. Here is one of the Hoover Dam that was taken using the Pentax LX on Kodak Ektar 100 in aperture priority mode lasting about 45 minutes.
Most all cameras with aperture priority can reliably autoexpose a scene lasting seconds. Few others can achieve minutes.