Earl
Red Fin engines have a show case and on-line store here:
http://www.redfinengines.com
The "Kompish" .5 cc Diesel TBR will be released as a production engine shortly. Twenty have been made for field testing and feedback from existing Red Fin owners prior to general release.
There are other engines in development, including a small flat twin diesel.
Chris
The only 'charcoal' case Doonside Mills .75 Mk. 2 I have seen is shown in a colour photograph on page 146 of the book "Gordon Burford's Model Engines" by Maris Dislers. So, there must some out there.