Lower rear shock mounts 67-72

[pritch]

I don't know what these are called. The pieces that the rear end U-bolts bolt through and have the lower shock mount holes. I started cleaning up the rear end parts on my Panel, and I noticed that the holes for the lower shock mounts were really egg shaped. I have a couple others floating around here somewhere, but my question is: Are there better ways to do this, I mean, a reinforcment mod or something?

And if it turns out that the other ones I have are bad also, are there re-pops available? Can new ones be bought?