there is a place in harkers shipyard in knottingley,only thing is i can't remember the name m8 but if you go into delta engineering on detla business park across the road and see kenny or tosh they'll tell you where they are.
or you could go to PMP metal products on the tanshelf industrial estate in pontefract....jim's son wayne builds custom midi moto's from scratch so he should be able to make you some up if you take the originals in
both delta and pmp are owned by friends i've known for years and are fantastic fabricators