Topband: Switch for 160 meter antenna

[Ken]

Hello,

I am building a 160 meter vertical antenna, and perhaps incorporate a 80
meter antenna within the same structure.

I would like to switch out a top section of the of the antenna by means of a
switch to break a connection leading to the rest of the above antenna
circuit.

I could easily do this with a relay, but I don't want to rely on any coil
failures either due to voltages drop out or weakness of the coil of the
relay.

What I would like to fine if possible, a type of wiper or knife like switch
that can be activated by a servo or similar type mechanical devise.

Does anyone know of such a switch, and where to fine it?

Thank you,
Ken
K3YI