Yes I would repair or replace it, and here's one that looks a lot like the OEM one on our Jayco

. There's a big difference between not having one and replacing or repairing an OEM one. Finding where to drive the screws!!!
Your damaged ladder probably isn't "through bolted" with plates inside the RV like we mount deck hardware on boats. It's probably held with stainless steel "sheet metal screws" into the aluminum frame structure of the coach. If the mounting points aren't damaged, it should be easy to mount a replacement ladder, or re-install yours with new parts.
These ladders are the same stuff used for aluminum bow rails, grab rails and Bimini Top frames on boats. A shop that makes "boat canvas" can make you a pair of new side rails. They often have to do special bends for oddball brackets. You can buy and assemble all the other pieces, rungs etc. I found this ladder with gOOgle "rv ladder parts" and there were oodles of hits. Seal it up good with Dicor under the mountings then over the screws through the coach body.
We don't have any camping "activity" that calls for getting onto the roof, but we find we need to often enough that I think a ladder is well worth having.