they are available for every month for the first year, 18 months and every year from 1 through whatever, although some are special orders
the history of chips is interesting, but since bill w didn't really like clapping or celebrating (it fed the ego) these aren't more than traditions created within each meeting....
Clarence had a medallion he put a hole in for each year of his sobriety, he was the youngest of the first 100 people in AA and his medallion had 46 holes in it at the time of his passing.
Sister Ignatia used to give a St Christopher medal or some coin to those in early recovery and told them to come and give her the chip back if they were going to drink.
A woman went to a bar to drink, she dumped out her purse and a chip was in it. The bartender asked what it was and she said it was her AA chip. He refused to sell her any drink and told her, "We don't serve alcoholics here," and showed her the door.....
Marbles were given out in the UK....something about "losing your marbles" began back then......
Do your own search on the history of chips! They've been around since the early days of AA!