mate you need to take the thing out to see what connectors its got on the back, if its got an Iso connector then the worlds your oyster. Not a massive job to fit one though. I dont think the newer models will have the same connectors on the back.
I have a 2001 SF and they are standard connectors. Probably easiest to find something in Halfords or wherever that you like the look/sound of and that suits your budget. A new one will be very easy to fit as it will come with the correct mounting cage as well. You may need to buy an appropriate removal tool to get the old one out (looks like the 2 pronged one), but again the tools are in Halfords.
Thanks guys - looks like the Double Din is out. I thought it looked wrong this was confirmed by Northernlight.
I think I would have to relocate Headlight washer, Headlamp leveller and a light switch. to create the right size appeture.
Interested to see pre-newage switchgear differences - almost prefer the more quirky headlamp adjuster and a proper "switch" for brightness. I also prefer the black/grey centre console surround, instead of the fake graphite thing I have in mine, which is frankly hideous!