I've tried to google every combination of "19thC British Army" etc and can't seem to find anything suitable
One suggestion is to digitally photograph some painted minis in the poses you need, then use a desktop publishing program to make your cards. Failing that, if you have a scanner and your cards are only going to be for your own use, maybe you could scan some suitable poses from books such as the Osprey series etc. Again, use a DTP program to incorporate these into your cards. Another possibility is to download pics of figures from manufacturers' websites and use those.
There
have been some cards made for "The Sword And The Flame", but they don't appear to be what you are after (only one standing pose).
There are also some cut-out card figures there in several "combat" poses which you might be able to download and use on your cards. They are Zulu War, but probably near enough to your needs.
Both these are available in the Colonial Wars Yahoo Group files section and you'd need to join up to access these, but if you are a colonial fan it is probably worth it anyway.
http://games.groups.yahoo.com/group/ColonialWarsHope that helps,
Ian.