I think it looks pretty good. I'm not a Bronco guru by any means, but did spend a significant amount of time searching for an affordable, solid Bronco last year. It can be tough to find a Bronco that isn't hiding a bunch of issues in the sub $20k market. Go drive it and see how she feels. I suspect the rockers rusted out and they we're removed, so make sure to check the entire body for problematic rust. Also, the doors have the lock key hole in the wrong spot to match a '67. That's something to discuss with the seller as well.
I picked up a very similarly built Bronco for $7500 last fall. The body on mine was in much worse condition than this one (dents and tube fenders). Mechanically had the same upgrades for the most part and drove solid, so I worked out a deal with the seller. You may or may not like the transmission, which is likely an NP435. I swapped my NP435 for an AX15 5-speed and the bronco is much more street-able. EFI helps too.
I think you can get a better deal though, so maybe offer $15K if you're still interested after driving it.
