Nickel pythons command a premium, so it's a good thing. Buy it and run it's a deal. Years ago I had a nickel python in 6" bbl with a patridge front sight and elliason rear and traded it away. Fast forward years later discovered it was a custom shop gun - no wonder it had such a slick action and pretty grips???!!!
The percentage of nickel guns produced versus blued is miniscule - I would suggest buying the nickel python and flipping it if you can't handle the purchase of both and buying your bright ss python and still have some money
left over.
Even better is to buy both - no decisions. Cash poor, Gun rich - the story of collecting.