European oilers wanted, prefer size 0 and 1, any condition, for restoration of a horizontal Perin & Panard slide valve gas engine.

Unknown French Built Engine

We first came across this engine around 10 years ago.  Little is known of it.  It is stamped with the number 1 on most of the parts.  The crank-disc is 12 inches diameter, the bore is 4 and a half inches.  We are 99% sure the engine is French as it has all metric threads.  The flywheel and head are not original, although the valve chest bolted onto the back of the head maybe. The engine has very small water inlet and outlet passages, approximately 3/8” diameter. The engine may have originally been fitted with an air-cooled head.

Any information would be greatly appreciated.