bcoldpro-
Can't say about the bumper.
If you want something bumper-like, but with some better features, you can look at mounting under the coach in a section of PVC fence post or pipe. There are a number of threads in iRV2 about this, some with pictures.
I used a plastic tote to carry my sewer hose and fittings- the same tote for both coaches over about ten years of combined ownership. It was about two by three feet by eight/ten inches tall. The hose fit inside the perimeter and the fittings inside that. When I sold the last coach the insides of that tote were unstained and did not smell. I had followed a routine to put things away that limited any kind of dirty water dripping from the hose or fittings.
I kept a second, smaller tote for spare fittings and sewer-handling tools, such as plastic wrenches. I kept a spare length of sewer hose, capped, in the rear of the electrical bay.
Both totes fit in the electrical bay, directly behind the wet bay. I kept the wet bay floor free of all items.
I may have a picture of the totes, but I noted along the way that the manufacturer had stopped making that model. You can probably find similar-sized totes online- ones that fit in one of your storage bays.
Finally, I chose sewer hose and fittings so they could be stored well inside a tote or collapsed. You may have to, or want to, change the manufacturer/model of your parts to meet your improved storage method.
I've yet to find one that fits in my bumper as the interior bolt assembly gets in the way.
You need to buy a specific hose that will fit into the bumper before the interior bolt. You need a 10 foot hose. You can buy 2 hoses and insert one each into the left and right sides of the bumper. Normally 10 foot is long enough for most sites, but if you need longer, you can connect the 2 hoses together to give you 20 foot. Of course you would also need the bumper caps to prevent the hose from falling out, The following hose fits and can be bought on Amazon:
Valterra D04-0113 EZ Coupler 10' RV Extension Hose, Red