Swapping masts and re-rigging

[Brion Toss]

Hello,
Unfortunately, none of the variables you mention, by themselves, lead to a meaningful answer. What are the loads? Do the moments of the old mast suit those loads? Are the moments of the new mast at least as large? The fact that the new mast was double-spreader might indicate that it is lighter, relative to the load; that's one big reason to go with double spreaders. But we just don't know, so any selection would be arbitrary at this point. I think you need a consultation before deciding.
Fair leads,
Brion Toss