I have an alternative to using grommits. I was using grommits to hold the elbows of the sight indicator. It worked fine except it was hard to find the correct size grommit.
I found a better way of making the sight indicator that will still use the same size hole.
This is a 1/2" PVC elbow for flexible pipe. It can be found in the sprinkler section of the hardware store. You will need two of them.
A long with 2 o'rings and one 1/2" male adaptors on each end.
Note: I cut about half the barbs off.
Make sure its the correct length and install it on the bucket.
Good luck, R.