The cheapest, lightest, best tubeless wheels you can build are Alex Blizzerks in either 70 or 90mm laced to Bike Hub Store hubs. This is going to blow right through your 200 dollar budget but you end up with better wheels by a long shot.
I have Surly My Other Brother Darryls on my fat bike which are made by Alex. They replaced Clownshoes which were huge and heavy. When I switched to the Darryls, it transformed the bike.
What's the drivetrain on that bike? I looked at the pic and it looks like I see a front derailleur cable. You could get a single ring from Wolftooth. If you lose the shifter, cable, front derailleur and second ring you could lose up to a pound. If it's already a single, then never mind.
In all seriousness, you could lighten up every part of that bike but nothing is going to be better than lighter, tubeless wheels.