You need to get some legit carbs ASAP before you burn it down. 156 main would be a Keihin style carb jet size. Most Keihin carbs I’ve run take 45-50 pilot and 155-165 main. So it’s probably not too far off.
Recreation is up since people aren't traveling. It's just a supply and demand thing really. Stock ones have always been high, but it's not a buyer's market right now.
Fox Podium rear and Floats in the front. Never look back.
If you opt to keep your OEM rear shock, you really don't need a revalve.
I have run OEM with different springs on everything from +2 to +14 arms.
What kind of budget are you looking at?
They are Warrior shocks.. I run Fireball drag arms.
https://www.ebay.com/itm/FOX-FLOAT-3-FRONT-AIR-SHOCKS-13-DRAG-RACING-LOWERING-YAMAHA-BANSHEE-350/382372142396?fits=Year%3A2013|Make%3AYamaha&epid=1134379311&hash=item590727dd3c:g:2K0AAOSw~oFXHqUv