It may be hard to believe, but, Fransisque Darne and Darne are two different companies that produced different designs of sliding breech guns at the same time.

Welcome to France.

The OPs questions refer to the former, the Stoeger company imported the later.

Although a base model R10 is no longer produced, 3 large wouldn't be anywhere near what a new R15 would cost today. Geoffroy Gournet is the current importer.

Best,
Ted