You should be able to get them through your dealer, however, if you're reluctant to do business with him, you may be able to find the parts you need online. One place (I've never dealt with this business) is here:
http://www.campersdirect.com/keyston...binet+Hardware
I have no doubt there are others, and quite often, similar and even identical parts can be found at hardware stores and Lowes/HD.