The feet are actually part of a brass knob set that I got at Home Depot in the US - the set comprises a knob, a surround and a bolt. I used the knobs elsewhere and had the surrounds left over. They make pretty good feet! I think those particular ones were for 1 1/4" knobs. You can get similar at B&Q, the difference is that the knobs I have are solid whereas the B&Q ones are hollow.
I'm now off to do some work around the house. :roll: But it will involve major woodwork