There is indeed a market for extra-tall frames, and they don't have to be the ultimate in quality either. One of my son's teachers last year is a big (6' 10") guy who loves cycling, and I helped him find at least one bike. There were a very few bikes made especially for the larger rider (Fuji had one model) but they're usually just the same strength steel sized up. Naturally a 250+ lb rider on such a bike hitting a pothole is going to stress the steel more than someone at 170lb like me. So my son's teacher has a small stockpile of bikes, which are more or less disposable---he figures that sooner or later they'll all break.
You might try cleaning this one up and selling it on CL with an appeal to the extra-large rider.
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I never think I have hit hard, unless it rebounds.
- Dr Samuel Johnson