I think David's analysis is spot on. For me it comes down to a cost issue. The most expensive solution would be to have a new set of wings made up to the original shape using the original technique. This preserves originality but means the electrolysis problem remains.
Both of the other approaches sacrifice the originality aspect in favour of solving the problem. Factory superform wings are the right material but the (slightly) wrong shape, fibreglass wings are the right shape but the 'wrong' material, in the sense of preserving originality.
Either solution is going to soak up a good few hours of labour unless you can do the job yourself, I have a similar challenge in that the old steel wings on my 1986 car are on their way out, I have been quoted £5k to replace them with modern Superform wings (all 4).
