Here is a genuine SU made gasket for the air intake on HIF type carbs. These carbs are used on a huge number of classic British cars from the 1970s.
SU HIF 38 HIF 44 SU CARBURETTOR NEEDLE VALVE METRO MINI
ROVER V8 SU HIF 38 HIF 44 HIF 6 CARBURETTOR GASKET & SEAL KIT
MINI 998 1275 SU HIF 38 HIF 44 HIF 6 CARBURETTOR GASKET & SEAL KIT
SU CARBURETTER REBUILD KIT - SINGLE HS2 - CSK51 - GENUINE SU
CLASSIC MINI GENUINE SU CARBURETTOR DAMPER DASHPOT OIL AUSTIN MORRIS HS HIF 4C10