Does anyone know of a cheap (<$60) adjustable humidity switch that, unlike the kind that attaches through ducting, has the ability to attach a remote probe.  I need to sense humidity on the other side of a wall about 4′ away.

Humidity is at room temp so no need for a “dew point” sensor or anything that adjusts RH for the temperature.

Ideally I’d like as a single pole switch rated for 120V and at least 1.5 Amps but would settle for a low voltage device if I had to (which I’d hook up to a relay).