FWIW, The famed Austin & Halleck Mountain Rifles are back.
Once upon a time, besides their modern inline muzzleloaders, Austin & Halleck made/sold a pretty fair Hawken rifle repro, called the Mountain Rifle.
It was only available in .50 cal, with a 32" octagonal bbl - but in either flint or cap lock.
Either flint or percussion barrels were made in both 1:28 conicals twist and a 1:66 round ball twist.
The stocks were also available is ascending grades of Tiger Maple.
I have a rocklock, myself:

Well, A&H closed their doors in 2006, and besides scarce, the price of Mountain Rifles found lately have kept up pretty well.
I don't know why it took so long, but it appears that Tradtions has purchased the old stock of the A&H Mountain Rifles, and is offering them on their website at an astounding low price, considering their quality.
http://www.traditionsfirearms.com/eshop/10Expand.asp?ProductCode=R910060sk
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