"GWI - Foreign Intervention" Topic

I've got a nice collection of Steve Barber's excellent GWI miniatures coming along well, of which I'm adding a few bits from Brigade Games Ottoman range. However, I'd like to add a small nucleus of units from the Foreign Powers (those supporting the fledgling Greek state, Britain, France and Russia for instance). I've been doing some research and the nearest I can find to support the Greeks are the Perry's Carlist war range. Be grateful for thoughts, ideas, advice etc on uniforms and ravailable ranges that I could use.
One of the scenarios I've got in mind is a small Royal Marine detachment landing on a small island in support of the Greeks either trying to break an Ottoman siege or enforcing a blockade.
All comments gratefully received!

Because it followed on so close to the Napoleonic Wars any figs in light kit would do, you could look at the two Russian figs from Steve Barber

Look at Parkfield Miniatures South American Wars range

For what you suggest, the Perry Royal Marines from the Carlist Wars range in their bell-top shakos would work very well. You can also use their Napoleonic sailors as well as those in the Brigade range. Empress also do some British sailors which are for the slightly later Maori wars and, for me, work a bit better. They fit with the Perry figures very well and they present a more uniform appearance as well as having their own rocket detachment in addition to the Perry RM one.

This is what I have used for anti-slavery raids in West Africa and plan some early Opium Wars raids. I hadn't thought of the GWI but will now. I use Sharp Practice for rules.

Many thanks to everyone for your suggestions and advice. Very much appreciated.
As regards rules, I find Sharp Practice is ok for longer games, but for sheer fun and fast play I use Sacre Bleu,