I not only have looked through this instrument, I know the present and previous owners.
One of our late club members, Jerry Knuijt, found this beast in a store room at Lawrence University, Appleton, Wi. He bought it from them and did a partial restoration and then installed it in his observatory NW of Appleton, Wi. I observed with him on a number of occasions going from the Clark to Jerry's 16" homebuilt reflector. I could go on about Jerry, but he's not the subject of this post. The Clark gave lovely views of the planets etc.
In his later years when he was in failing health he sold the 10" Clark to another club member, Gerry Kocken. Gerry loves to restore old and preferably big telescopes. He purchased a 16" J.W. Fecker Cassegrain along with 2 5" Fecker refractors and a sweet 3" Bardou refractor a few years back from another local private observatory.
Gerry has lovingly restored the 10" Clark but I have not seen it myself. It is indeed a very nice example of the Clark's work.
P.S. Gerry also has a 4" Clark that he got from yet another Green Bay area observer who passed a while back. Don't think that's for sale.
P.S.S. I do believe we used 1.25" eyepieces on the 10" but I won't swear to it.