lexmarks567.
I don’t recognize the brand name Brittany, many distributors come up with their own name for Bikes made for them by one of a few manufacturers.
My best recommendation is, just take your wheel off and to a repair shop. They frequently salvage parts from bikes, and you very likely can buy a used assembly, which will work. Take your original Chain with you, where you can fit it around the Sprockets of the new wheel, just to make sure you have the gauge matched. If the new rim is European, you can always drill the Valve Stem hole out to American, if that’s what’s on the front.
The rubber Belt (sometimes called a Snake Belly) can be purchased separately, they’re very flexible, I’m sure you can find one that will work. Tire being the same, not that many variations on 26”, but of course you’ll need to get the rim first, and go from there.
Have a good Day !
S.W.