CB750F1 rear brake caliper parts

[martin_uk]

Looking for suggestions.

DS are 9.25 plus vat each for genuine rear brake seals .

Does anyone have a cheaper suggestion for 38mm piston original pn 43209-371-006

Also need a 38mm x 23 mm piston with large groove for dust boot   original pn is 43205-371-006

Thanks

[Bryanj]

See if your local bike shop deals with Hi Level wholesaler and ask if you can look in the big catalogue to check out piston sizes