Interesting device. Top marks for ingenuity. Kind if a cross between a Sherrif of Nottingham crossbow and a modified bicep flex trainer!
Outboards of the size this could work on, say 3.5hp to 50hp, then I doubt there's a market for it especially as space is already a premium on board boats up to 4m. Even If you had an injected molded carrying case for the starter, plus the drill case, then that's kit to store you don't actually need.
There could be a market for marine workshops. God knows they must see their fair share of pull start outboards for servicing at the end or start of the season. That said, most outboards, especially 4-stroke, around 15hp up would be electric start these days I'd have thought.
My own view if it's a pull start outboard, then you should be able to start it by hand. It gives an indication of how long it takes to start the engine, service ready, fault finding, etc.
Anyway, best of luck with it.