I agree- check that frame real close...if they dont mind, tap along the bottom front under the doors with a soft faced hammer, and in front of the rear tires- they can rot anwhere, but those are usually where it starts. even if theres no rustholes, dont be surprised if the hammer goes right thru...sadly these car's frames werent designed to drain very well, and (especially seeing it sitting in high grass keeping the underside damp) if it was EVER in roadsalt, I'd bet >90% odds the frame is going to be bad. When my mom and dad got our 69 in 1972 or so, it already had rustholes in the frame, just ahead of the rear tires - the car held together till I wrecked it in '79 but just sayin... they tended to rot faster than a chevy vega.
I would love to find one that was clean, from a saltfree area, IMO those cars had the coolest dashboard Ive ever seen (except for the stupid lefthanded radio)...
no idea on 'worth', but I'd guess IMO if the frame is OK, body very solid, even if not running somewhere in the 2k range tops. 1k probably would be as high as a lot of folks would go as its not anything special options-wise
FE could probably get it for $5