Buffon is our captain, he will not be benched to be rested because he doesnt need to be rested as often as the outfield players.
We dont need a sub euqlly good or nearly as good as buffon right now...because he will be terribly expensive and i cant stress this enough; he will not get playtime. If is a rising keeper on its prime...he will have to accept the bench anyways... but then we will have to deal with the wage problem, and impretty sure we will up our wagebill for the outfield players next season.
Is way better to have a decent enough keeper just in case buffon injures, but not a stellar keeper. The only way i can see someone coming, if he accepts the perennial cold bench for a year, and even then we will have to pay some good wages.
Anyways, in that case, we should go for some midtier level keeper like Perin or sumthing and be done with it. if not keep neto or audero.