That's where I got my replacement rudder last summer. They will offer all sorts of options - most of which will make the rudder not class legal (e.g. Carbon and lighter core - but why do that since there is a minimum weight). Tell them you are not looking for any special materials or a balanced design (not class legal), just good construction practices on a one design compliant rudder to insure no water intrusion. I had the rudder made with the standard vinyl ester material they offer on the baseline rudder. The mounting hardware and hole locations are not standard across different boats. From my experience, here are some suggestions.
1. Ask them to provide the stainless steel sleeves epoxied into the rudder for all locations where hardware passes through
2. The location of the tiller pivot point needs to be precisely measured and located so the hole can be drilled in the correct location on your new rudder. You can do it after the rudder arrives, but you are better sending the information to them so they can drill and isolate the hole. If this is off, the tiller or stainless bracket mounts will interfere as the tiller is raised and lowered on the pivot. See my attachment in
this old thread to see the type of dimensioning needed.
3. You can buy new mounting hardware, or the old ones - I reused the old stuff. If you are reusing the rudder hardware, take precision measurement on the location of these on your existing rudder. It's best if you can send them the hardware from your existing rudder so they can precisely locate the mounting holes. It's amazing what a few thousands of an inch can do for the aggravation factor on getting the rudder back in the correct pivot location.
4. Only have them drill the holes for the lower mount. See the reason in number 3 above. The lower mount can be sleeved and epoxy isolated. Once the bracket is mounted, it is used as the reference for holding the rudder in place to locate the upper bracket.
5. You can shim and hold the rudder in position with the upper bracket in place, then drill the holes. I marked the forward hole 1st and drilled it. Then I attached the bracket with 1 bolt to hold the bracket in place, and drilled the other holes. Look at
this thread and associated Blog entry and you can see how I added the isolation sleeves after the season. Since it's the upper mount it is less susceptible to water intrusion.
6. Gelcoat color - the rudder will come white. If you want another color, stripes, etc you can work with them to have that done, or have it done locally. I did (or am in process of) my own gelcoat stripes. I still have yet to wet sand and buff the stripes.
When you visited
CPYC in October at the NAs, the Rhapsody rudder you saw was about 2 weeks old. It had not been gel-coated with the stripes, and the upper mounting holes were not isolated - all that is done now.
Good Luck!