FYI - Here are the images along with the description from the "American Indian Tomahawks" that Okwaho mentioned:
I'll agree "almost" whole heartedly with Okwaho - with one exception (howdy Tom - I'm the Gray/Grey Wolf from the Frontierfolk and HT boards)and that is that not all gunstock warclubs were diamond shaped in cross section - note the one at the bottom in the above image which is flat.
The diamond cross section is generally eastern while most Great lakes and western ones I've seen and handled are normally flat (there are always exceptions to any rule - note the Chippewa accredited club above)). Here are two examples of flat sided clubs - both appear to be made from Osage:
As to paint - for a period correct Indian paint mix red ocher and bear oil together and rub it by hand (note to Tom: this is the mix Nita recommended on a post a while back and is one I've also used successfully on both wood and leather).
Red Ocher is also available from Crazy Crow (their red earth paint) or Sinopia - an art store who supplies several colors of earth pigments to the trade. Both have on line stores.
Another option is to mix the pigment with linseed oil if you can't get bear oil.
For Eastern - I would use either black (ground hardwood charcoal) or red - I've seen originals that although most of the color was worn off had evidence of those two colors being used. Western as you can see even used green, but that's most likely fairly late.
The blade position on originals varies from the flat edge as seen in the first western image to the bend as seen in the others.
A favorite blade used by western tribes was the NW Company's early double sided dag/bayonette blade and the later Hudson Bay Company dag blade. Both blades were made in various sizes with one existing Osage club collected in the 1820's having a blade about 9" long by 4" wide!
One last note - the gunstock warclub used in the Last of the Mohicans was about 30% oversized for screen presence - most originals are around 30" long overall.
Scouts out.....