I was just about to replace the washers on my mini AFCK as well. For those of you who don't have a micrometer, here are the measurements:
Factory washers...
large: .654"OD x .225"ID x .026" thick
small: .375"OD x .225"ID x .026" thick
Sheffields carries BP washers, .005 thick with ODs of 1/4"(.250), 5/16"(.3125), 3/8"(.375), 7/16"(.4375)
and IDs of 1/8"(.125), 3/16"(.1875), 1/4"(.250)
A little quick comparison shows none of the washers Sheffields carries have enough OD for the large washer, but I think the 7/16" should suffice. the 3/8" OD will work for the small and in both cases I am going with the 3/16"ID and drilling it out to the required .225"ID. Since the only thickness is .005" I will just use a stack. I will let you know how it turns out.
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