the louvers make it difficult and costly to make I would think
Costly yes, but there are guys that do that. If you can't find an original, that is the route that I would take.
Of course, right after I shelled out the beans for the replacement, an absolutely trashed parts cooler with a perfect cover would show up for like - "come and get it for free"
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That's what just happened with my C51 last fall.
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