Jshorter, about finding a paper patched mold...
As long as you're staying with round bullets, having an inexpensively obtained second or third hand (smaller diameter) mold machined to a larger smooth sided cavity of your chosen nose design and diameter is as good a way to go as any. Producing a rough finish on the cavity (to help the paper stay on) isn't a bad idea.
When machining out a smaller mold to make paper patched bullets the big question is how big does the mold diameter need to be to give exactly the desired cooled bullet diameter. Ah but wait, you can't cast a bullet ahead of time to check for shrinkage because the cavity isn't big enough yet. If you can machine it out to almost final, and cast with it for reference numbers and then final machine it then yeah, you could do that. But if not you're stuck with sizing after paper patching. And if you're going to do that with a smooth sided bullet then some surface roughness can help the paper not slip.
I've sized smooth sided .40, .58 and .69 after paper patching. About ready to have an old mold remachined to use in my .458" bore (.470" groove) rifle.
Hey, by the way, have you tried paper patching castings that you currently use lubed?
Taking them down to below bore diameter after patching shouldn't be a problem with a good quality push though sizer.