These clips for the 7" dexter
brakes are hard to track down. One of my clips was broken on a NEW dexter
axle replacement that was installed on my
Trillium 4500. It took me a while to determine that was the problem.
Ajax Trailers in Warren, MI had a dozen on hand. I bought 3 or 4 from them.
So look for a utility trailer shop or horse trailer shop. There are probably several of these shops somewhere in Chicago.