Jeff,
I posted one of these when you were making your rudder pedals.
Knowlton and Ottawa using the same clamp and spacer arrangement with centering clamps on the pump not the 'P' clamps that everyone else seems to use. No idea what sources others use but I'm pretty confident that the photos are accurate. This is what I used for my pump. Note the difference in mounting ie one above and one below the tube mounts.
Regards,
John