The Current British Army 'Snow-Cat' is the VIKING BVS-10
Kits:
There were rumours that Cromwell Models were doing one in 1/35.
I've seen his Challenger2 & FV432 Bulldog with Bar Armour, at Telford IPMS, BUT my memory is unreliable as to IF he did do the Viking.
1/48th BVS10 by HLBS looks good!
example here of BVS10
BW Models do a 1/76th Alvis/Haggelunds Bv206 The BVS10's predecessor, but still current.
BW Models do a BV202 ('Original' Sno-Cat) Build here
More Pics here