Very nice Ben.
Objective may be 180mm f.l, f/3.6 so eyepiece 26mm f.l about.
5 or 6 element?
If really 77 deg AFOV then field stop may be 34mm or 35mm.
I wonder if really 11 degrees or nearer 10 deg.
May be a lot of edge distortion or angular magnification distortion.