I replaced my existing bumper after I smashed it while backing up into a light pole
Bought an appropriate length of 4" square tubing stock from the local steel supply. It was either 1/8" or 3/16" thick. Then went to a welder and he beefed up and added the frame attachment pieces and welded everything up. I painted it all black. Entire cost was under $100 for a sturdy, functional bumper. The end covers/inserts still fit.
Personally, I would never store a sewer hose in a bumper for several reasons. Rust being one, plus most sewer connection fittings will not fit in a 4" bumper. At least none I've ever owned. I store all my sewer hoses in a plastic bin after rinsing them.
Scott and Liz - Southern NM
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