you could check out sew n so's , they make bags for all accessories, if you give them the dimensions they can make you a bag to fit and not expensive ,padded or non padded.
I bought a bag for my aquaroll and another for my awning poles last year from bags4everything. They come in a choice of heavy duty or lightweight. I opted for the heavy duty and was impressed by their quality. Not expensive and delivered within a couple of days. The company is run by Gardners of Wakefield
We don't put our dish in a bag - we have a plastic circular patio table that we use with the van, and it stores under the fixed bed (without the legs of course!). The sat dish rests perfectly on the table, face down. With a few things placed strategically round it it never moves or suffers any damage. A much cheaper option than a bag!!
Suggest you take a trip to IKEA they have storage bags for all sorts of stuff, I use one of them for my dish it supposed to be for a duvee or blankets but its just the job for almost anything with the zip closure