Here is a nice wood kick up rudder assembly for your Potter 15.  The rudder is made from solid mahogany and will work perfectly for you.  The cheek and head assembly is also made from aluminum.  Stainless steel is also available at an increased cost.  The rudder is coated with a minimum of 3 coats of spar varnish.  The tiller is laminated from ash and either black walnut or mahogany and then covered with a minimum of 3 coats of spar varnish.   I do include pintle with you verifying locations.  $325.00

We now also offer sunbrella tiller covers. Check them out.  http://www.jowoodworks.com/archives/boat-parts/953