I think that not only would there be a problem with sourcing the correct or alternative Herc engines but also the propeller assemblies as the nearest type to have the Herc engine was the Bristol Freighter ‘Wheelbarrow’ but that had a four blade where as the beau is a three.
Then there is the Tail which is not a five minute job by any standard
Plus ‘little’ details like getting tyres made
I would think that restoring a Spitfire is ‘childs play’ relatively speaking in comparison as parts are more common place along with experienced engineers merlins are more plentyful etc.