You might check pricing at WalMart online:
235 80R16 LRE is $104.92
https://www.walmart.com/ip/Carlisle-...10PLY/55012162
235 85R16 LRE is $123.21
https://www.walmart.com/ip/Carlisle-...10PLY/55012160
They also list 235 85R16 LRF, but there is no confirmation on the item page that does confirm that it's actually a 12 ply tire. It's listed at $121.02
https://www.walmart.com/ip/Carlisle-...5R16/118765859
I've ordered my last 4 sets of trailer tires from WalMart and found they are the cheapest pricing and comparable tire manufacture dates. They don't remove/install wheels on trailers. The reason, as I was told, is because they don't work "outside the service bays" and there is not enough room to pull a trailer into the bay. So, up to you to remove/install wheels. I do mine in the driveway, one side on jack stands and one side on jacks/wood blocks (I keep saying I'm going to buy another set of jack stands, but so far haven't found them on sale since HF stopped their 25% off coupons.
Anyway, check WalMart, you might save a few bucks and with their road hazard policy, you can get a tire replaced/fixed most anywhere there's a street light.....
ADDED: It's been my experience that most RV dealerships don't do "tire work". They farm it out to a nearby tire shop, so if you're expecting the dealership to "remove/replace your tires" chances are what they'll do is jack your trailer using the leveling system, remove all 4 tires, drop them off "down the street" and then go pick them up later, reinstall them and charge you "double for their trouble"....