www.thetford-europe.com click on service and scroll down select repairs and any other bits you want remember the one pdf for toilets covers all current models including the c2.3 &4 older bench type. Download and save the pdf select your or enter your toilet model if you don't know you'll have to look through the pdf to see which matches yours.
Still stuck then send them a message on 'ask thetford' on the listing
bob Lunar owner, September 2012
