You should probably look at a map. A Caravan will go feet wet in Canadian airspace. The Canadians have regulations for for North Atlantic ferry flights found here
Backgrounder: Safety of Small Aircraft Flying Across the North Atlantic - Backgrounders - Backgrounders, Reports and Info Sheets - Media Room - Transport Canada which are based on the North Atlantic International Operations Manual found here
http://www.nat-pco.org/nat/CurrentNAT%20IGA.pdf Neither of these require the pilot to have made a prior crossing.
There are plenty of companies that have experience in North Atlantic ferries and can cover the FWI-Scotland or just Canada-Scotland leg for you.