Interesting. I bought dust covers for my dust-sensitive equipment. Now this is a Dutch shop, but I’m sure you can find something similar where you live. They make dustcovers by hand for every product you can think of, and you can also give them dimensions. They’ve lasted me a good while now, and they’re cheap too!
The website is really ancient, and so is their billing system, but it works 
. (they actually send the product through mail with the receipt, you have to pay after receiving the product. WIN!
Good customer service too, had a problem with 1 cover and they sent me a new one for free 2 days later.