First off: I was joking about the marble contact, stainless is where it's at. I know it's going to look like ass after a bit of play, but 3M stainless steel polish works wonders.
Cost: I was quoted AUD$80 for the one long CP, 2 short CP's & another 100x100 panel with lots of little holes in it including material. Material is 0.9mm stainless, brushed finish. As the laser place ended up borking my timber cut somewhat I got them for free. I'd suggest sending CAD files to all the laser cutters in the area, as I had quotes on the timber cutting vary from $140 to $888.
Bolts: If you look closely you'll see there's only 2 bolts/stick, I just used them to hold it in place for the photos. Final version will use dome allen head bolts, either chrome steel, or stainless. Black steel if I can't get either of those.
Buttons: I put the two holes where the black buttons were as an afterthought, and to balance it symmetrically. I think I'll use them for pause and escape. Coinage will be via 20c coin door (wired to both '5' and '6') or shifted IPAC function. I put 1UP and 2UP next to each other as there are also two vertical CP's that have no start buttons (plus P1Start + P2start = escape if I want to use that shifted function.
Joymonkey: How thick was your panel? Mine's .9mm, I hadn't considered csking before. Yours looks great, I'd never seen another stainless panel in my searching before.
I'll bend up the panels next week which will give some much needed rigidity, but right now it's time to break out the router and start building.