I contacted WD about the tuners listed above. They had me send photos of my headstock, and got back to me with the following:
“To my eye, I believe out of the ones that you have looked at the Gotoh is the closest.”
He did include the spec sheet for those tuners with the precise dimensions. At least, I think it was the correct spec sheet. The ones from their website have a SKU of ML3-G, whereas the spec sheet lists part number SG381. I don’t see those two numbers matched together anywhere. Overall, this doesn’t exactly exude confidence, but I’ll dig out my digital calipers and try to confirm the screw placement myself.
I also spoke with my local guitar tech today and went over all the modifications I’m planning to make. He thought it all sounded good, aside from the Delrin nut. He said they make their own bone nuts, and he’d recommend that instead.