You are very kind, MacBean,

I just scored a two tone (blue w/black facings) Regulation doublet, myself, and am eager to see it and discuss it further, but first I must pay the piper and the postman, too.

CmcG, I have looked at a lot of tailcoats on eBay and I worry that you'd have to look at a lot more to find one that is a) the right size, b) made of wool, and c) cut the way MoR describes- with a single breasted closure. I expect it would be simpler to go to the tux shop and inspect the rental return stock firsthand. I am sure they are out there. I do think that I'd start with a tailcoat to make just about any kind of adapted doublet. If you are lucky, you can find one that is cut in such a way as to make adding the skirts on the front simple. I expect the fabric in the tails should be plenty to make them and any sleeve treatments you may want to make. I certainly like MoR's ideas, whether you "do it right" and bespeak the thing or cheat a little by remaking an existing garment.

One other idea I'd consider- look at and fondle as many jackets as you can- take a lot of pictures if you are able. If you are going to rely on a helpful sewing person other than yourself, be sure to make them as familiar as possible with all of the arcana of tashes, too. You might even find it worthwhile to pick up a doublet that is inexpensive, but not your size- even a piper's tunic, just to see how they are constructed.