ALL convertibles are keepers in terms of value.

If all you need is a door, you can use one off of a hardtop and graft your window "caps" and vent assembly to it.

If you like the car, the best bet is to strip it down and PROPERLY repair the damage.

I had a '68 Galaxie convertible, Cayman yellow, black interior with buckets and console, 390 2V, C6, front discs. It was a great car and I regret trading it for a '68 Cougar 390 that I parked shiny-side-down.