You can get the very latest British 24hr Rations direct from the manufacturer called Multi-Climate Ration Packs.

http://rations.vesteyfoods.com/ration_packs.asp?ptypeID=4&packID=6

The older style rations can are available here (but these rations will most likely be a 1-2 years older than the MCRs.

http://www.surplusandoutdoors.com/shop/a...ent-687979.html

I used to get my 24hr ORPs locally for £5 each but are now not available. I would probably go direct the supplier at Vestey foods as the additional extra cost will get you the newer rations. Many of the older items have been replaced as described here,

http://www.army.mod.uk/news/14369.aspx

So no more biscuit browns, biscuit fruits (which I actually like), chocolate bars, powdered soups and Oat Biscuit etc which are more adapted to colder weather northern European environments.

The MCRs do look quite good though.