coldene.com
https://coldenecastorsandwheels.co.uk/product/noise-reducing-sandwich-castors-swivel/?attribute_pa_diameter=100mm&attribute_pa_top-plate=105x80mm&attribute_pa_hole-centre=80x60mm&attribute_pa_overall-height=128mm&attribute_pa_load-rating=150kg&attribute_pa_wheel-bearing=ball-bearing