Coil spring refresh?

[spannerrash]

Hi all
Whilst I'm doing some other work in the front wheel arch area of the car, I have decided to remove the front struts to give them a bit of a cosmetic refresh. Re-paint etc. As with many cars of this age the coil springs have some corrosion. Especially around the bottom coil or two.

Normally I would just replace, especially as they are 18 yrs old and are probably suffering from some "work hardening" fatigue. Unfortunately they are NLA and I cannot find any aftermarket supplier's for the sports suspension. I want to stay as near stock as possible so am ruling out coil overs.

Back to the main point / question. Can old springs be Re-worked? I'm thinking heat treating to reset the stresses and bring back the original spring rate and then some kind of protective coating.

Doable, not doable, stupid question?

Thanks Frank

Not thinking of doing this myself by the way but farming it out to a specialist company, if I can find one.