here is the ebay link to the head unit, it is a generic Chinese double din head unit, the part numbers appears to be 7021G
The G refers to it having Satnav
The same basic unit as been around a couple of years and they have gradually added features, the latest ans greatest is the 7021G
It cost be £58 delivered from the uk
I also bought a camera for the rear view which was £6 delivered, so all in all not a lot of expense on the electronics
http://www.ebay.co.uk/itm/131895695660?_trksid=p2057872.m2749.l2648&ssPageName=STRK:MEBIDX:IT
cheers