cheapskate here, but I would definitely take it for 200. The brake is pretty minor fix if the head tube/fork look fine--and that is the key point as it is odd that somebody put the new headset in. Other than that doesn't look to me like it was ridden much, no worries about specific tubesets, my 1988 560 doesnt have any 531 but still a great rider. At your size it should fit and the buyer pool for that size is pretty limited so see if you can get it for 200 if the head tube/fork look ok.

edit, also this looks like 1984 vs 1987 and as such all components must have been added or custom? 501 frameset but was not spec with 600 gear though it was out in that era as on my 84, 85 fuji so guess it may have been built out like this originally if picked up as frame. 84 had the unreliable rear heliomatic hub so maybe check that. All points to lowball city, go for it!