not to pull a shang tsung, almost a year after the thread was opened, but I figured I had to comment here, with what I know about the British army from the period 1740-1764:
the mitre cap, and I'm not certain of this, is likely from the 2nd regiment of foot. the CR makes sense only in this case, since George II's wife was Queen Caroline. the royal warrant of 1751 makes it very clear that the mitre ought to have the queen's monogram, with a garter round it, and a sea green facing (the shade of green in the photo is pretty close-if faded). the queen's cyper and garter motif was also on the flag of the regiment. here is a quote from the warrant:
"On the Grenadier Caps, the Queen's Cypher and Crown, as in the Colours; White Horse and motto "Nec asperra terrent" on the Flap.
The Drums and Bells of Arms to have the Queen's Cypher painted on them in the same manner, and the Rank of the Regiment underneath."
mind you, this particular feature was confirmed as being official-so it was already there prior to 1751.
because of the lack of a number on the band, I'm inclined to say it's pre-1751, when numbers were ordered placed on the back of the band-which was to be sea green in color of course.
but as mentioned at the beginning, this isn't certain: the CR and the color are what I'm going on.
the bearskin is easy: it's from the 50th regiment of foot. the warrant from 1768 makes it clear that the number of the regiment was on the back side of the bearskin. 50 in Latin numerology is L of course. the size makes it likely from the revolutionary period, though as mentioned here, similar patterns were present as late as 1812. the presence of the trophies motif (drums and flags) points to it being a drummer's cap-something a couple of users have already alluded to.
again, I'm going by what I know.
discuss.