I'll quote myself from a few years back since it basically fits the OP's question and CA's comment above:
"+1 on charlieaarons’ comments. I don’t know if you are committed/restricted to a beadlock 335/80/20 on your 550 chassis (camper?) but another, easily sourced and maintained, option that Ive been using successfully is a 315/80R22.5. I have a custom leaf and coil suspension (Pohl Springworks in Spokane will build based on your rig’s spec and put it all together very professionally) on my F550 and use Continental 315/80r22.5 HDR2+ (summer) and HDW2 (winter). I have 8 Alcoa wheels I swap seasonally. They are relatively easy to find in stock, not too expensive new, very easy to order, try Pete’s tire store on the web. Performance-wise, the weight rating and speed rating of the Conti 315/80’s are higher than the 335/80 options (not that the 335/80 are inadequate in either respect on most rigs I’ve seen), the winter tire traction on snow and especially ice is excellent. I would be very interested to see much of a difference in offroad performance between my setup and another ~16-18k lbs 550 camper using a 335/80r20...given ~equal drivers, the suspension capability as well as vehicle weight/size might be more important factors limiting mobility: i wouldnt expect to see a significant offroad advantage either way, unless we are talking about unchained driving in snow/icy conditions where a softer compound siped-tire really works well."
I personally wouldn't want MPT81 or equiv military beadlock tire for extensive snow/ice driving unless I was really wanting to run the "chains on/chains off" drill on a regular basis for a crossfit exercise. I will also add that Continental for the past couple of years has been struggling to supply tires in the US for some reason though apparently they are releasing a new/improved MPT81. I am likely switching to the following tire unless I see Continental fixing whatever supply/production challenge they're facing:
https://business.michelinman.com/tires/michelin-xdn-2-grip. My 315/80r22.5 are L-rated (9090lbs and ) and 75mph speed rating. The 315/80r22.5's are very durable tires though they can't be run at extremely low air pressure like an MPT81. The weight of an ER (for a fully loaded trip on a newer ER, maybe round it to ~13-14k on the rear axle and ~5-6k on the front) doesn't come close to the load capacity of these tires which is where I prefer to be versus crossing my fingers that the MPT81 or equiv mil tire can handle the weight on and offroad. I will add that there are plenty of ER owners who use the MPT81 with success and they are the ones who really stay on top of the maintenance. These folks do quite a bit of offroad travel but I've never heard anyone speak much about the snow/ice capability of those tires. Note that the 315/80r22.5 are ~43". I don't know if this will work with ER's standard kelderman 6x airbag lift.