Good morning, E. von Hoegh;
Thank you for the reply. Unfortunately, that is the same address and telephone number that is in the Richter literature that is here already. Even more unfortunately, the telephone number "has been disconnected and is no longer in service."
That is why I had asked on APUG, hoping that by reaching out to a much larger number of people, I might encounter someone who may actually know the Richter family or possibly may know of someone who might still have the objective lenses available. I did hear a rumor that Tom Richter's son might still have the equipment, and, hopefully, possibly even the drawings from which I could perhaps make up a substitute objective test lens, if I can get a copy.