Buy nice or buy twice.
127 mm is really wide by modern standards. I'm thinking you are going to find it difficult to match that BB. You probably are going to have trouble getting the front derailleur to work. If it was my bike I'd bite the bullet, get the crankset that you want and whatever bottom bracket it takes to match.
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My greatest fear is all of my kids standing around my coffin and talking about "how sensible" dad was.