They can be hard chromed but it if done properly will be bear the price of a new shaft.
To repeat what I wrote earlier, the best information I was able to gather is that hard chrome plating will not
stand up to the pressure put on it by the rollers. I got this information from people who do hard chroming for a living and who understood the question I was asking. If hard chrome would have worked to build up the main shaft of my SCT2 I would have had it done rather than risk buying an aftermarket part. As it turned out, all the measurements I did on the shaft I bought from Autocycle, which can be found somewhere within my Spitfire thread
, showed that it met all the dimensional and hardness specs.