Extenders via EBay is currently selling Pedal Commander Throttle Controller for various Vehicles for $299 - $30 instant discount - $30 EBay Bucks (Via Current EBay 10% EBucks Sale) = $239 YMMV
I have not seen these selling for less than $299 anywhere. Unfortunately they didn't have one for my model but there are quite a few on there at the sale price.
Recommend looking at YouTube for what this Pedal Controller does. Seller currently has 15,115 reviews at 100%.