Star Warp ramp split into two is WAY better than no Star Warp ramp. I say go for it and if I wasn't clear about it before, feel free to cut those ramps up I gave you anyway you see fit in the name of science. That sounds like a pretty workable solution to me. That in-between bit was really the main challenge/obstacle, right?
As far as machine shop access, I've got it. That's not the hard part though. The hard part is for someone who knows mastercam or another professional CAM software package to sit down and design this mold from scratch in excruciatingly precise details. If I could get that drawing, I'm pretty sure my friends at the machine shop would be glad to sit down with me over some beers and work up the toolpaths and knock one out on some Friday night. The likelyhood of this is pretty low though. If I sat down and designed something on Google sketchup for instance and took it in there, the guys would just laugh and say "we need to redraw this entirely, there is no point even attempting to import it".
Split ramp is way more likely than any of this. They could even be designed with an overlap where they could be screwed/riveted or otherwise fastened together which should make them stable enough to mount with only the existing stock holes.