Hello there Dave, we would be more than happy to make these parts for your engine! Here is a link to our Facebook page so that you can have a look at some pictures of similar traction engine projects we are working on at the moment, we are actually doing some work on an Aveling at the moment so would be very interested in doing some more!
https://www.facebook.com/MWSteamEngineers Hope to hear from you soon.
Best wishes
Ryan
Michael Webber Steam Engineers
michael.webber@btinternet.com