Not that tough to rebuild...Same as a 2 stroke. Getting it out is more time consuming though. Tank needs to come off so you can get to everything. As for the choke you can make due with whatever wrench you can get on it or modify one to fit. I have an open end wrench that I ground down to fit and I know another guy who ground down a box end wrench to fit. Basically made a cut in the end so he could get it over the cable.
Get an aftermarket kit that includes the needle and seat since that is most likely the problem. Polaris doesn't sell a kit, just the individual parts. If it leaks with the fuel turned off too, I think you are gonna want to replace the fuel shut off also.
Mine: 2018 Sportsman 850SP - 26" Bear Claw HTRs on OEM steel wheels(I really don't like the Aluminum ones)
Polaris Hand warmers, Mirrors.
Hers: 2019 Sportsman 450. 26" Bear Claw HTRs on Moose 427X Wheels.
2007 Sportsman 500 EFI, Polaris Winch, 25" Bear Claws QSC Clutch Kit, Hand Warmers
2001 Magnum 325 MOSE 12" rear wheel conversion. 25" Sedona Coyote tires
2017 Polaris Ranger 1000XP - Roof and front glass
2018 Kawasaki KLR650
2001 Magnum 325 Warn winch and Moose 60" plow-Sent to Daughter and Son-In-Law since his blew up
SOLD 2004 Sportsman 600 Twin