Distributor Rotor

[Bruce of MN]

I took the cap off my distributor to check the resistance between the points block and chassis ground per a current thread (~1 ohm) . When I was putting the rotor back on * , I noticed that the brass piece was slightly loose. When I got out the rotor from my backup dizzy, it was loose, too! The plastic next to the brass piece was chipped on both, too. I tightened the rivets on both, but will get new rotors.

Is this a common fault with repro parts?

* I have to confess that I have forgotten to put the rotor back on a couple times.