Any idea what specific event this was used?

@oak would be able to chime in. I got a few loose pieces from him as gifts.

Used mostly for raffles and such. astarias provided a story at the bottom of this page:
http://o-review.com/forum_detail.php?ID=10571&p=2

Ohh man thanks bro..

Are these common? I have never seen these wooden chips

“Not common” would be an apt description. I’m sure reps still have a bunch of them in their storage somewhere. They’d probably give you a roll if you know them and asked for it. My rep gave me a few years ago.. I broke 3 rolls and gave most of the coins away, so they shouldn’t be too difficult to find.