Gaggia Classic Steam Tap to Boiler O'ring - 996530054245 From  £0.72

Appears to work well

I was shopping for spares for a 1988 Gaggia Espresso made in Italy.

Although it has had the odd simple descaling, the machine is entirely as purchased. Having looked at various videos recently, I decided that it deserved a boiler descale, a new gasket, and a new group head gasket.

I did not use it during the service, and do not know if it fits the Gaggia Espresso of 1988 vintage!