relay to control line voltage device with low voltage switch?

["james" <nospam@xxxxxxxxxx>]

I need to control an appliance (120V 10A) using a controller designed to
switch low voltage device. So I need to add a relay in-between.

Is there any pre-packaged relay that includes a low voltage output (that can
be used to power the relay), a 3-prong power cord, and a 3-prong outlet?

I found something called "honeywell switching relay" that seems close to
what I need but doesn't have a power cord or a 3-prong outlet. Although I
can wire those items myself, I prefer a unit that comes with them. Any
suggestions?