I have purchased the sickle shown in the picture below at the gardening section of a hardware store the other day.
I did not find it by accident, I was actually loking for it there since I have seen a few of my dojo mates using this exact brand (simply a standard industrially manufactured tool). Most instructors I have seen usually perform with more thick and apparently heavier Kama. Some of them use to carry tools exactly as the one in the picture for semminars or keep them in the dojo's closet to be used by those who do not have their own yet. Possibly because these are very low-priced so any damage they suffer would not mean a big loss.
By the way, it costs less than US$3,00 each.
So, is it common for you (your dojo, your association, etc.) to use these type of tool in practice or would you rather use the ones strictly designed to be used as weapons? Does the kama shown in the picture look decent? I just wanted to know how usual is that in other places.