We have these great new-old-stock scott-mathauser brake pads made for the low-mid end brake sets of this vintage. Weinmann, Dia Compe, Universal, Gran Compe, Suntour, etc.
Please read the info on the back of the package in the 3rd photo for any info you need. Or message us if that doesn't work out. Either works.
Check out our great collection of used/NOS cycling parts and accessories, you may find something you want/need!