Hi Skippy,
Looks to me rather like an incomplete model of a Walton Yacht Works 65 foot HSL built for the RAF Boat Section around 1942 - 46. The number 1228 puzzles me though🤔
Maybe she was an early prototype/trials version?
Only one of these was ever commissioned by the RAF, No. 2642.
She's the only RAF boat I know of with that unusual foredeck/cabin arrangement.
BTW; I suspect that the 'dustbin' on the stern of your model may have actually been a twin barrel gun turret 'borrowed' from Bomber Command.
She should really have twin screws as well, Twin Napier engines, 30 knots.
Cheers, Doug 😎
http://www.rafboats.co.uk/hslw65.html