Chrome restoration question???

[ca77]

I am restoring an old motorcycle and in the getting ready to re-chrome some parts stage. The exhaust headers and mufflers have small dents and gouges in them. My question is, is there a product available to fill these problem areas before buffing the metal prior to new chrome? The parts have already been stripped to bare metal. Am I stuck using a welding torch and filling it that way and crossing my fingers these 45 yr. old parts won't warp.
Any advice at all is greatly appreciated.