Given how impossible this sort of thing is to find, the best answer may be "whatever you can get in less than 18 months". The Coleman units seem to be pretty popular as replacements. They now sell under a couple of brand names due to being part of a larger "group".
I might be interested in the defuser that blows the air inside the trailer, if you're replacing that part as well. I'm looking for a older version style for my 1996 if they are the same.
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