How muck time does it take to replace an intake manifold gasket. No air on 1991 Chevrolet Camaro

I'm told 3hours shop time. @ $100 an hour. Is that a fair price? plus $30.00 for gaskets. $330.00 Total

Asked by for the 1991 Chevrolet Camaro
5.7 on the other car now it is a 5.0 engine? Same deal, small block chevy. but which one you got? That's not a bad TOTAL price!