If one accepts the Nostratic superfamily hypothesis (linking Proto-Indo-European to other families such as Semitic), then the galgal connection to keklos makes perfect sense. Of course, once a group had the wheel, I guess contact with neighboring language families would occur much more easily, so even if it's more than coincidence, it would be hard to be certain whether it's a borrowing or cognate. Nevertheless, that both words have similar meaning and both have velar stops, liquids, and apparent reduplication makes me agree with the cognate hypothesis you both made.
This result from a Google search reinforces the hypothesis; the following collection of roots includes "krikos" and "galgal."
http://www.angelfire.com/rant/tgpedersen/kr.html