Call Overtons 1-800-334-6541
I got my Clarion CMAS-2 from them. Its a standard size unit. Comes with a wired remote also in the package. You could keep it for a spare or install it somewhere else later.
It is a great sounding unit.
The Overtons part # 27657
There is a pic on there website also at www.overtons.com . They will overnight for 12.99 + normal ground shipping.