Bob,

I say yes you can paint up your alternate choices. I have not really considered the muskets or detailed equipment but a good paint job should suffice to convert them.

____________________
References looked at

Osprey Montcalm's Army
Osprey The Austro-Hungarian Army of the 7YW
Images on google for the various armies (many ripped off Ospreys)

___________________
Other Possibilities

Most tricorne hatted troops would be close enough so I would also consider:
1. Revell's French Infantry in the AWI
2. Airfix's Washington's Army
3. Tricorne hatted AWI figures from other manufacturers and Strelets GNW range
4. Hat Spanish Napoleonic Grenadiers (look like the 1750's French Grenadiers)

Have a great day, Frank