I have seen on eBay genuine and non genuine Focus centre consoles with and without folding armrests. Try searching, the UK forums (
www.ffoc.co.uk), and the US focaljet site.
Try this one...
eBay Focus armrest
I have also seen (probably on the UK forums too) that there is a way of disabling the seat belt chimes. Something involving clicking the belt 20 times or something with the key in certain positions. Never tried it though.
Enjoy your Focus.
MK