You searched for "field replaceable"
RS PRO
RS PRO Compressed Fiber Gasket, 115mm Bore, 229mm Outer Diameter
Part: 268-3004
Industrial gasket for sealing pipe flanges and equipment joints reliably.
RS PRO
RS PRO Compressed Fiber Gasket, 43mm Bore, 82mm Outer Diameter
Part: 268-3109
Full face compressed fiber gasket for industrial equipment sealing up to 350°C.