A tiller pilot would be a good option..... except he stated he was currently using a Navico WP100... which is for wheel steering, I believe.
Although I prefer the Simrad/B&G products, you might want to check out the Raymarine EV100 p70 unit.... I found it
here for $1000. Shop around for other deals if you like... or go price match the item at WM if you choose.