Get a length of 4mm thick ground flat stock, 1"1/2 wide. Mill the width down to 33mm (if you can get away with a width of 31.75mm, just get 1"1/4 and no milling involved). Then take it to a local wire EDM place and get them to slice it down into 1.6mm pieces. Quick rub of all faces on some wet and dry placed on a flat surface, jobs a goodun.