Hi! I'm looking for a part described in the photo below for an old Unitron scope. It is a plastic tube like piece that unscrews from the ota and holds the diagonal. I'd like to get one that will accept a 1 1/4" diagonal. I don't even know if this part is available so let me know if I'm barking up the wrong tree. This is such a wonderful scope that I'd like to try some larger eyepieces in it.
Thanks in advance for any help!