Well, everything CAN be repaired. I myself would look for a clean West coast frame but the right man and the right welder can repair and reinforce that area.
I have seen the upper back tub (under your tank) break but any point can just give up.
Are you a bigger guy that jumps allot?? Poor suspension can harm a frame all the time if that is the case. Just blown out fork seals not fixed until they HAVE TO BE FIXED, can be a bad thing for the frame itself.
Kasey probably has a nice frame he'd part with; Seems to be a talented, fair and reasonable guy. Send him a PM if you wish.
But, DO NOT just throw 2 plates on it and weld it up if you want to fix rather than scrap it. It all must be cut out and a new down tube made up or chopped out of another 85/86R 250R.
I myself at a FAT 5'10"s 220lbs am quite surprised that I have a 350X with TRX450 linkage rear suspension that I designed and I have no gussets even on my own 350X frame!! It was just a time thing, I'll get to it but I'm amazed I haven't broke this late 86 350X with some OEM gusseting just yet........
All our government does is distract us while they steal from us, misspend our tax $ and ruin our country