There is a company in California which does Subaru conversions for Vanagons (US name). I did some research on them and would consider using them for a TDI conversion if I ever got another Vanagon despite the fact they are on the wrong side of the continent.
Anyway, they are called Fast German Auto. They can be found at (not too surprisingly)
www.fastgermanauto.com. Their address is Fast German Auto, Inc. / 2911 South Oak Street / Santa Ana, CA 92707. Their phone number is 888 - 211 - 3334. (I don't know the international prefixes you would need.) Their e-mail is
sales@fastgermanauto.com.
While they do Type 25s, I would imagine they could answer a lot of questions for whatever application you had in mind.
Good luck,
René