[Folsom]

http://classdaudio.com/amplifier-modules/mini-class-d-audio-power-amplifier.html

No volume pot. Used, but like new except it sounds burned in 

$32 shipped.

It doesn't say but it has mute function, you can wire your own volume off-board and switch some jumpers. The quality of the product is very high. 

[Doublej]

How about this?

http://www.amazon.com/HY-502-Digital-Display-Motorcycl-Amplifier/dp/B0095N6K0W

I think there are lower end ones in this family of products but they may not be adequate from a sound quality perspective.

[srb]

How about this?
http://www.amazon.com/HY-502-Digital-Display-Motorcycl-Amplifier/dp/B0095N6K0W
I think there are lower end ones in this family of products but they may not be adequate from a sound quality perspective.

Doublej, why would you post a link to another amplifier in someone's Trading Post ad?

Salis Audio, another good reason to follow convention and prefix the subject title with FS: in case someone doesn't realize what circle they're in.