the heli-coil is probably the best option given they value of the cranks. In the interest of keeping the superbe pro cranks going I would explore that route. A local shop should be able to perform this job.
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1 Super Record bike, 1 Nuovo Record bike, 1 Pista, 1 Road, 1 Cyclocross/Allrounder, 1 MTB, 1 Touring, 1 Fixed gear