The 35/2 didn't change much between 1965 and now, at least in the manual focus lineup. Even the single-coated Nikkor-O version is a solid performer. As solid as an AI or an AIS, in my experience.
With respect to the 50/1.8 AF lenses, the worst of the bunch is the newest version. Very cheaply made. Same optics as the Series E and compact AIS lenses, though. The second version, called the AF 50/1.8 New is the lens to get, if you wanted an AF lens. Has a double row rubber grip on the focusing ring and a little thicker plastic barrel compared to the D version, so it won't flex if you squeeze the barrel between your thumb and index fingers.
AI lenses have a longer focusing throw than the AIS lenses, which will make it easier to fine-tune the focus. One of the reasons why my 50/1.4 and my 24/2.8 are both AI lenses and not AIS lenses. I've never used a Nikon that required them anyway. All the bodies I've owned and used that had P or S modes were AF bodies, which can't use those modes with AI/AIS lenses.
With respect to KEH, you can use them for buying stuff. You may get soaked on shipping, but, if you can have someone in the states receive the package, then send it as a gift to you in the UK, it might be worth doing business with them.
-J