If you can crack the code on this one, let me know. I've been scouring the internet for like six months and have met with limited success.
Your best bet is probably Sideshow's Revolutionary War Redcoat - 64th Regiment Foot. They sell on eBay for $250+. That said, it looks great and is definitely on my list... Maybe when my tax return comes in...
You can try Soldiers of the World, as mentioned above. They sell on eBay for as little as $5, but you get what you pay for... I've never found a detailed review of one, and that in and of itself tells me a little about their quality. If you try one and find it works, please let me know.
There's also Greystone's 1745 model. I'm not a big AWI buff, so I can't say whether this uni is "close enough" or could be modified to suit. It's another entry on my "maybe one day" list. You can get them on Greystone's website, but they are usually on sale cheaper at Cotswold's.
I already asked Amy at AJ Clothiers if she'd make me one, and she replied that she doesn't usually make uniforms. I'm sure Le 1/6 Zouave could whip one up... They're cheaper than tracking down a Sideshow figure. I've seen lots of beautiful British figures from Tony Barton, but I've never seen a pattern or tutorial. Tony, if you have one, please share!
:goodluck
And for all the manufacturers out there: We need more Regency / Napoleonic models! Hell, just make us the unis and we'll do the rest!