That might be a tough one. I would look on the underside of the sink and see if you can get a manufacturers name, then contact them to see if they offer any other options. If there is no name, you might contact Lori Penland email@example.com and see if she can help. She's the parts manager for Crusader there at the factory.
Forgive me as I am not at all familiar with the Crusader line. However, I can tell you that Platinum Sinks makes many of the common RV shape/configuration/dimension sinks in stainless. DW doesn't like the plastic in our Heritage Glen either, and I found Platinum after seeking a replacement. We have the solid surface countertop so we want to preserve it and the sink closure inserts, and FR did not have available a stainless sink to match the shape.
Residential and RV sinks will almost always be slightly different, you will most likely need to do some modifications to install a residential sink in a RV. On the other hand the choices are almost limitless.