Please Help First 42 re rigg querry

[Cariboo raven]

This forum has been a great source of info. Here is my dilema.
I am looking for advice on sizing the backstay on our Beneteau First 42 (1984). It is a sloop rigged masthead jib Isomat mast with double spreaders. We are re rigging in California and the suppliers here are hesitant to supply or source out the 1/2" wire and swages to replace the backstay. The backstay is adjustable. Their recomendation is that 3/8" 316 wire will suffice as the forestay (furling 153 jib) and the inner forestay (non furling staysail) caps and lowers are all 3/8" wire. The intermaediates are 5/16". The rigg is done using swage fittings all around. do I really need to have a 1/2" backstay any advice or direction to advice would be appreciated, Thanks

[svHyLyte]

All of Beneteau's rigging in the US is provided by Seco South, see SECOSOUTH, INC. Manufactures of stainless steel cable handle rail systems

Note, however that all rigging on the First 42 except the lower shrouds is 3/8". The real trick will be sourcing the right toggles and pins.

Regards,

s/v HyLyte