TF - Stock Bench Seat Shoulder Bolts

[Dan in Pasadena]

I am reassembling my stock bench seat after having it blasted & powder coated gloss black. It had one original, useable shoulder bolt. Another one was in a spare bench seat but it was stripped. The other bolts had been replaced with assorted bolts and EFFED up the holes in the frames - had to weld repair them and re-drill.

I bought a Lang thread chasing set from Amazon. Says "Made in USA - Racine, WI" - Anyone used this company's tools? Good/bad?

Picture is AFTER I chased the threads. They weren't so much stripped as flattened. Would a true die fix the threads further OR do I need a replacement original bolt? Still available? Source?

Sorry the pic's loaded sideways. The one on left (or bottom) is the one I chased. It's a LOT better than it was but I don't think reliable long term.