It's not that bad to re-cut the threads. It's commonly done on the old Raleighs to go from 26 TPI to 24 TPI. That left 3 good rows of threads, and 3 is enough to hang an integrated bottom bracket onto. For Swiss, at 25.4 TPI and a slightly larger diameter, there may be 5 rows of threads intact after re-cutting. If you use an ISO threaded BB at 1.375" = 35mm rather than a BS at 1.370", then it will be plenty tight.

OP- Where did you pick up yours for slightly less than $70?