Indeed the Warlord (ex Conquest 500 nations miniatures?) are truly excellent sculpts and with a bit of judicious rummaging in various lists, especially Boothill Miniatures Mexico, Empress New Zealand and Perry Cape Wars ranges, proxy substitutes can be found. However you need to take the "film director's" stance and think in terms of flavour rather than outright accuracy. All of the above are superb miniatures. That said there are plenty of gaps: Here are my suggestions for what they are worth:
Seminole Indians/ Creek Indians
1) Command Pack Oceola mounted, dismounted chiefs, medicine man.
2) Villagers – Women folk and children, (crouching hiding would be a useful figure pose, as well as walking etc.) These are absolutely essential for skirmish gaming as proxy white settlers can be found amid Perry's ACW/ Cape War ranges but nobody does Seminole/ Creek villagers and civilians.
3)More Warriors are always useful.(muskets/ clubs and bow and arrow wouldn't hurt).
4) Wounded, carrying wounded fellow warrior, lying wounded.
5)Warriors in dugout canoe.
6)As suggested above, mounted Seminoles.
7) Escaped slaves with rifles and hand/ improvised weapons with command.
8) Escaped slaves casualties.
U.S. Regulars/ Militia Volunteers etc.
1) Regulars in a variety of hats(straw hats/ caps)as well as 1833 folding "Hog Killer" forage cap/ 1825 "Wheel spoke" pattern forage caps etc in Firing line and charging with the bayonet poses.(usual strategy for breaking through the Seminole line).
2) Command in various forms of Campaign dress.
3) U,S, Regulars casualties, assisting wounded comrades, lying wounded etc.
4)Camp scene around camp fire with camp followers/ Military surgeon etc.
5)Mounted Dragoons with Colt revolver Carbine, with command.
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6) Mounted Horse holder and rider less horses.
7) Dismounted Dragoons with Command, with Colt revolver carbine.
8) "Irish Volunteers" and "Brisbane Blues" state militia with Command (Plate E from Osprey MAA 454).
9) U.S. Sailors landing party with Command. Armed with the Jenks rifle.
10) U.S. Marines landing party with command. (Plate H from Osprey MAA 398).
11) Creek Indian guides and allies with white recognition scarves around heads and arms.
12) U.S. Sailors pulling at oars/ manning Carronades to go with Laserdreamworks U.S. Gunboat.
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13) U.S. Sailors and Marines in canoes
(see "Swamp Sailors in the Second Seminole War for details of this).
14) 6pld Artillery and crew in campaign order.
15) Civilians – "Cracker" White settlers/ farmers as well as gentry/ plantation owner and family, southern belle etc.
Serrissa Precision do a superb Surrey cab/ carriage crying out for these.
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This represents and absolute dream "wish list" on my part but hope it helps to encourage discussion on the range and maybe some of the suggestions make it onto the table top! Wish you every success in the venture, oh and can we have a UK distributor.. the weak pound is killing us this side of the pond on top of ludicrous handling taxes and charges! Evidently items marked "toys" don't get stung as much, "miniatures" are considered antiques and taxed accordingly.