Mark incase you don't already know. The original spacer washers 15-7045 are 0.155-0.160" and the thinner ones for the metric bearings are 0.105-0.110". I guess you have the ID and OD, but I have that if required.
I imagine that a bigger stock of the thinner ones would be favourite these days.
Finally I managed to find some time to run a few thinner bearing spacers off. These were machined from a medium carbon steel.
I don't know the price yet but they won't be much. In a few days they will appear on https://pesltd.uk/ as 15-7045A
If you buy the bearings from us Anita will put one in each bearing box for free. That will be listed as 26-6890