Installed new MC (big PITA) from Eric on my '73 and rebuilt the rear proportioning valve at same time. Finally getting a nice firmer pedal but have some niggling drips from top of valve and from banjo fittting on the MC.
Got some new washers from Stoddard but they seem very small compared to the original ones.

Was going to get my good old 40 year old parts catalog out to look up the numbers for the washers but figured someone here may know a good source...

TIA

Why not try Eric for washers? If desperate, harbor freight sells a copper washer kit that might have the size you need.

Ditto on what Mike said about Eric. Call him first.
I have too have that HF box of copper washers. Comes in real handy.
If those fail. Try McMaster Carr on the web. They have just about everything. Quick service too.

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Sorry for the size. When I resized them they went blurry.