Hi Scott, am I the Doug you directed this towards? (I assume so since I posted to the old thread!)
I started looking into making an alternator to look like a generator a while back but quickly ran into problems. The OD of typical alternator stators are simply a lot larger than the case diameter of the Lucas C40 generators. There are some very compact Denso alternators with small stators but they are somewhat expensive, particularly if your intent is to take them apart and use their parts inside a generator look-alike. There are also a few alternators available that require external control boxes... they are compact but parts for them didn't appear to be readily available.
I also considered getting a motorcycle alternator and re-packaging one of them. However, they are seldom rated in Amps. They are typically rated in Watts and no one seems to be able to tell you how fast they need to turn compared to a car's alternator... so I tabled that idea.
When I looked at buying steel pipe for this project (for the shell that would house the alternator components) that was rather expensive even before machining. In the end... I just gave up. There is the U.K. product which is horribly expensive. There are also the "similar" looking U.S. products from PowerGen. They are made for GM and Ford applications (and may therefore be too big) but they are about 1/2 the cost of the U.K. product. I didn't see how I would ever be able to find the right combination of components to keep the look and be cost effective.