Baroque, being related to Arabesque prizes symmetry in the natural forms (very thoroughly planned, meticulously created to be exact) Rococo tended to be an offshoot of Baroque and sought to emphasize the beauty in natural asymmetry (similar subjects and elements, just done in more of a free-flowing, natural design where tasteful "errors" aren't really seen as errors). In carvings, there is a big grey area in which genre one might place a particular piece, as there is a lot of overlap in time and place and even the same craftsman. Furnishings and paintings are a different matter, as one tends to see a color pallete shift, in addition to certain stylistic choices.
Some Baroque is Arabesque, Some Baroque is Rococo, all Rococo is Baroque, but not all Baroque is Rococo.
Modern repro's are limited because the people building them choose to be limited to copying a couple of surviving American examples, rather than creating their own. Anything carved in Europe could have been done in the Americas, if the customer/owner wanted it. As also mentioned, much of the architecture and decoration of American guns ventures into the folk-art realm, not dissimilar to European guns of the late 1400's and 1500's. My thought is that as the European gunmaker's industry became more refined and "standardized"/condensed in the late 1600's and into the 1700's, the more localized folk art went away, and makers adopted forms that would be more appealing to a broader customer base (not dissimilar to the reduction of distinct localized beer styles/ingredients in the mid-late 1800's when "big" breweries started looking to make bottling and export a notable part of their business). Eastern Europe, Africa, and Asian gunmakers seemed to retain more of the folk-artsy forms and decoration; but gunmaking, as far as I know, tended to remain more localized in those places for longer (like it was in the America's)