Clifford
I have made new tillers for my last 2 boats, so the issue is not who makes it, any reasonable joiner will be able to create the shape needed, made easier as the old one is still in one piece.
The only issue is obtaining a piece of suitable hardwood. I used ash for my first and a piece of mahogany type hardwood for the second.Some hardwoods such as sapele are short grained and weak. Ash is very strong and tough but discolours if the bare wood is exposed to the weather. Teak would be excellent but may be difficult to obtain.
Good luck with your quest.
Philip