Dear @All, hope you are well.

I'm looking for some help/recommendations. The tiller on my Parker 31 (Nondikass) is broken and unfortunately rotted inside, so gluing it back together isn't an option.

Does anyone know a reliable workshop or person who specializes in making new tillers?

Thank you!
Mihaly Ganz

Your tiller looks as if it was the wrong wood to start with.
Teak is the obvious first choice but virtually unavailable. Iroko is the usual strong substitute and generally available from timber merchants. Any carpenter/joiner or DIYer who can use a plane and sandpaper can shape a replacement from the pattern of your broken tiller.
I made a new tiller for my superseal, and other boats before, it's not difficult.
Philip
The rascal, superseal

Any builder of wooden boats is likely to be able to make a tiller for you, a smaller business is a good bet.
An internet search should find who is close to you, try looking on the Wooden Boat Builders Trade Association site.
Alternatively if you ask around wherever your boat is kept, word of mouth will probably find you someone to help.

Martin