I bought a box of six sets and the price including shipping works out to $9.51 per set. One comment - the wood grain quality varies. I had one really nice set, one that was a close second, a third that was pretty good and the other three were OK but had the color of butterscotch pudding! They fit was good and they feel great.
I think these grips fit guns with serial numbers starting with 151, which cover most Sixes except the first few years.