I think most folks are missing the point with "PC". If you can make a story that does not involve time machines, you're just about 90% of the way to "Period Correct". Using an item, particularly a major visible identifying item (uniform, gun, etc.) that is later than the period depicted is what is not "PC". And using an item that requires a wild and improbable tale ("I was washed out to sea and ended up in west Africa and got my knife hand-forged there and then came back on a slave ship before heading to the west to trap beaver") is not advisable.
Example- what gun should someone portraying Jedediah Strong Smith carry?
Jedediah Strong Smith was born in 1798 in Bainbridge NY and ended up going west to join Ashley. If someone portrayed him as a young man in 1820 or so with a NY halfstock flintlock stocked in walnut or cherry, I'd be impressed. If someone was portraying him as a seasoned mountain man in the mid 1820's they might want to go with a standard trade rifle like the New English pattern.
A 7 pound "hawkins" with a 28" barrel might not seem as good a choice but what the hey.
The "PC Police" are largely myth- who here has been "busted" and told they could not attend an event?
The usual problem that always repeats itself is that someone shows their gun and asks, "when and where is it "PC"? Then folks who know explain the actual period and place in which such a gun fits, and the owner howls. Sometimes that time and place is, in reality, between 1970 and the present, anywhere Thompson Center or CVA guns could be bought. But saying so, even when it's the truth, seems to be the "wrong thing to do".
Most folks start out building up a set of gear and worry about where it all fits in much later. That's good, no problem. Plenty of events and rendezvous to attend. Knife, hawk, rifle, "skins"- good to go.
When that same person wants to portray a character in the French and Indian War, they should be genuinely interested in putting together a kit that fits, or maybe not ask, "does this fit?"
And of course, everyone is free to listen or not to the free advice given.