1/2" diameter and a tiny bit over 1/2" tall (15mm tall x 13mm diameter).
Hint: this also works as a 3-lb coffee can in 1:12 scale, which is 7" tall in full size. See below for one of these cans with a label from the Vintage Pantry Labels Half Sheet.
These are also included in the Matchbox Cabinet Kit; see all the other kit components available to buy separately.
Sold individually (well... a set of can and lid).