A 66pax International is going to be somewhere around a 30k GVWR. If retitled as an RV, no bus should require a CDL. $2500 seems to be a reasonable going price. Pay special attention to rust, on the body, undercarriage, floor, wheel wells, etc. Rust is a time and money pit.
If you could share what engine and transmission it has, we could be more critical.
You have to have a few posts under your belt before you can upload images. It's an anti-spam measure.