So the part number for the Canadian MFD+/DIS is 5C6-920-850-C (not mine, the full DIS)
On the buttons: I can trade for the GTI wheel and airbag which includes both side buttons. If the harness attached to the buttons is part of the steering wheel then I won't have a problem. If the harness attached to the buttons is part of the car and not replaced when the steering wheel is then it may be short one connector for the right buttons. The GTI wheel is leather vs. the V-tex leatherette that I have so it would be a nice upgrade.
Also I did read in a forum somewhere that adding the right buttons would work at the same time as the buttons on the wiper stalk.
I'll try and look at the GTI MFSW and pull my air bag over the weekend and compare.