Brazing some fill and retapping would not be an inexpensive solution. It's definetly a machine shop job just to add the filler and then bore it on axis in prep for the threading. And cutting big, fine pitch threads is not something that is easily done by hand so again you're likely looking at another shop bill. All told it had better be a pretty deluxe frame to justify the price.

I'm currently in the same boat with an older Cannondale touring frame. I'm either just going to retire it or buy the Velo Orange BB. The only other thought is to fire up my shop machines and produce a press in threaded sleeve and then to set up the frame in my mill and bore out the BB shell to take the press in sleeve. And that is only practical thanks to the generous wall thickness used in the early Cannondales. More likely I'll just do the Velo Orange BB thing since it would be FAR less trouble and cost.

I lookat at that Loctite thread repair stuff. Reports of using it here on BF and other places did not make it sound worthwhile for THIS application. LIkely it's something to do with the fine threads and large diameter but it didn't work out well at all.

The other thought is that if the BB threads in OK and you can torque it to the minimum of the desired range of torque then do that and call it good. Threads like BB's seldom are a precise fit and it's not at all uncommon to have some play in the threading. Just grease it up before you do this. And if it strips out when you are trying to torque it to the spec then just consider it as a preporatory reaming operation to better take the VO BB....