I accidentally ran across this yesterday while researching propellers and thought it might be of interest. The company popped up on the forum back in 2011, but it looks like their offerings have advanced a bit since then.

An Italian race engine developer called EPA Power sells three hopped-up Rotax 912-derived engines. Big-bore cylinders, Motec ECU and fuel injection. Available normally aspirated (SA-R917Tir) at 120hp or with your choice of turbocharger (SA-R917Ti) or supercharger (SA-R977Ti), both at 135hp. They claim to have ~50 engines in service, but there's no info about pricing or a dealer network.

Engine info is in the PDF documents here: https://sites.google.com/view/epapower/download