2014 V7 Stone Transmission swap compatibility

[RD350c]

My 2014 V7 Stone makes whining noises, will jump out of gear and there was significant metal powder when I changed the gearbox oil.  It usually rides OK, but I am always feeling that something's going to happen.  I'm reluctant to take it on long trips. 

I am considering sourcing another unit on eBay or somewhere else, but I am not getting any feedback from suppliers on compatibility.  I realize that the the newer 6-speeds have the same overall ratios, but there are no older 5-speeds to be found.  What models will fit my stone and about how many hours would the swap take?
thanks

[Off @ 90]

I doubt the Mk2 6 speed gearbox could be swapped  with the 5 speed . There were some changes -
the gearbox output shaft was lowered 50mm so cradle frame was lowered also the engine was tilted forward 4 degrees forward . Sorry to be the bearer of bad news .