It's very rewarding to make your own tiller and a small enough project
to get you interested in doing other projects around the boat
Tiller shape is a mater of preference mostly, assuming it clears obstructions easily, as your lifting tiller should. Length is usually the mitigating factor.
If you elect to make one, there are a few processes noted on line, though it's easy enough to sort out, if you're reasonably handy in a wood shop. The first step is to make a form. You can do this on a bench or table top, with wooden blocks screwed down to form the curve(s) of the tiller. Next are the laminations. Most use mahogany and ash or other light colored wood. I've done many over the years and I use pine for the light colored wood usually. Use fairly thin thicknesses as mahogany doesn't like to bend as well as other woods. 1/4" to 5/16" are pretty common. Butter them up with epoxy
and clamp them to the jig. When dry, you'll pop them off the jig (mold) and machine it to the finished dimensions.
It doesn't have to be a laminate either, it could be just a pretty hunk of what ever you happen to have. Preferably straight, tight grain, quarter sawn, with no defects (knots, pith pockets, etc.). Two pieces of wood glued together at the forward end, but made into a fork at the aft end, so it can grab the rudderhead or bracket will also work
In short, work
it out in your head
. You don't have to spend $400 on a tiller that cost them $100 and is using $20 in materials. Heck a length of pipe will get it done in a pinch, so give it some thought, maybe a father son project
, but hell a tiller is a walk in the park, just wait until something really important breaks . . .