Yes, that was a great run!
There was a time when Ed, the original maker, was on here and he supplied us with great tips, stories and photos of the real thing.
since we haven't IDed the real oil pan, and it looks like ed did some casting and shaping when he made the parts, my first bet would be that run.... seeing if sjanish still has molds or parts.
If not, I actually want to say this would be very do-able from scratch. I just made a control box for the energizer saber from scratch and it actually worked. As someone who never developed those model-making skills... I'm encouraging it
You could either built it up with solid wood/acetal/metal, some milliput and some sanding and shaping. Or, build the main structure from styrene, fill the inside with resin and use milliput or something to shape the rest. You could even go a step further and mold your scratch built part so the finished one is one solid piece.
I made the original structure by cutting styrene and using the little jar of "plastic weld" to make the frame and then sticking it in some clay to fill the inside with