Dutch Beaumont Pupil Rifle. What is it?

[KneverKnew]

I’ve been wanting a Dutch Beaumont Carbine for a while for going on woods walks. Then I saw this on auction. A Beaumont Pupil Length single shot rifle. The sights are different from the long rifle, and ive only seen the name on the Wikipedia write up of the Beaumont’s. I’m hoping someone knows a thing or two about these, if they are more scarce than regular rifles and what their value might be. Thanks for any help.