"Relope" is unlisted by the latest revision of the OED as well as by the magisterial, multi-volume "English Dialect Dictionary" of ca1900.

Nor do they include anything similar.

My best guess is that "relope" was an individual mishearing (and rationalization) of "elope" (run away).

The OED derives to "rollick" provisionally from a blend of "romp" and "frolic." What is more interesting is that the word doesn't appear till the 1780s or later.

I imagine that "gally-pin" and "rally-pin" are simply intended as nonsense words, possibly inspired by "galloping" and "rollicking."

Steve, Edith Fowke collected from a Canadian lumberjack ca1960 that contains, IIRC, "gallopin', rallopin' dandy." If you're unfamiliar with it, I may be able to dig it out.

If not, I can dig it out and post it.