A work colleague just told me about this place
http://www.mod-sales.com/
They're based in Grantham, Lincolnshire, and are the Ministry of Defence's authorised agent for disposing of military surplus vehicles and other items. Going by their website they've just sold a fleet of 100 Saxon armoured personnel carriers. According to my colleague, they also have a number of WW2 era items.
Obviously in a T2K timeline the World's armies would be more likely to hang on to stuff rather than sell it off as surplus, but there's a possibility that some older kit would still end up at places like this which could be a treasure trove for marauders or local militias.
Cheers