You could build your CP out of MDF and attach a piece of 16 guage steel (that matches the top dimensions) to the top of the CP.
You could get a piece of 16 gauge steel from your local metal fabricator for $10 and attach it with carriage bolts.
The pic below illustrates how you can mount the joysticks and buttons in the steel, and have it made rigid by the wood.
(the pic is the bottom of the Gauntlet CP, metal on top, wood on bottom, a vinyl CPO goes over the metal)
5/8" wood + 1/8" steel = 3/4", for 3/4" t-molding
Dig it?
Craig