Maybe try www.gj-agri-ltd.co.uk
They do parts for Richard Western spreaders but I asked them wether they could do a kit for our old Sampson. They have done in the past they said. Could be a possibility.
May only need adjustment. Same number or similar shows up on our puma cvx every now and again. First time it happened a few years back we got the pads changed as our dealer had no experience before with this, but found next till no wear on them.
I think there’s a tie up between frank ogg and a company Mallinson of Dalston Carlisle that make transpread spreaders and bruisers for Kelvin Cave too developer trailers. They’ve a post on Facebook end of June about it.