I was going to link you to the cover I got for my Wife's car, but its no longer listed on amazon. Plenty of others like it. Its a multi-layer cover that protects against water and dust, but is breathable. Its worked well thus far.
Its very similar to this one: https://www.amazon.com/BLIIFUU-Protecti ... B07D33TC9G
Which is some generic chinese brand.
The issue you may run into is finding one that fits an LJ well as its bigger than a TJ, but smaller than a regular SUV.