re: Creamer - he did supply to the fur trade via the traders Bryan & Morrison of Cahokia and Kaskaskia who in turn outfitted much of Manuel Lisa's 1809 expedition so Creamer's rifles may very well have been part of that expedition since Lisa outfitted his free trappers with rifles.
re: free trappers - there were in fact two levels of free trappers in the trade and this has always been a source for confusion:
1) Skin Trappers (Joe Meek's term): these were the men who were grubstaked by the company in return for a share of their catch - thus they were not completely independent, but neither were they employees of the company- they were rather analogous to sub-contractors. This type of free trapper can be documented for both HBC and the Americans, and is the type associated with the Manuel Lisa Expedition (see Thomas James' Journal) and the first Ashley-Henry Expedition (per Thomas Hampstead's letter).
2) Trappers on their own hook (G. F. Ruxton's term): these are what we today so often consider free trappers. According to all period documentation they were the smallest percentage of all trappers, never being more than 10% at most of the overall number of men in the field - many of whom were not even trappers but rather camp keepers and other such employees of the companies. Men on their own hook would include Bill Williams, who often trapped on his own but would also at times hook up with larger company brigades for various reasons such as safety in numbers when entering areas known to be hostile. Most of these trappers on their own hook were a larger component of those worked the Central and Southern Rockies where while there were some hostiles they were far fewer in number and less influenced by the Brits as was the norm in the Northern Rockies where Bugs Boys, the Blackfoot, held sway untilt he late 1830's when small pox almost wiped them out.
Two of the most prominent early Pennsylvania builders who sold to the western market were Dickert, later Dickert and Gill, and Deringer.
One final word - when considering the western fur trade, remember while there was a flurry of American activity going up the Missouri after 1807 it pretty well ended in 1812. During the War of 1812 (1812-1815) and for some time after, there was little fur trade business going on in the west by the Americans because of the war and the hostility of the tribes allied with the British. Astor's American fur after a brief foray west in 1810-12, didn't start going up the Missouri again until 1818 and the Santa Fe trade was practically nil until 1822 (prior to that you usually wound up in a Spanish prison for years), the same year Ashley took his first group to the Northern Rockies.
