Hey guys, I need some explaining on camber plates. I messed up one of the bolts oon my d2 coilovers, one of the three that mount the coilover to the body of your car. I can't find a replacement bolts anywhere in this size, d2 doesn't offer them, so one member suggested to buy new camber plate.
I just bought new shocks for fronts so I'm thinking why not grab a new camber plates and have a brand new coils in front
Now I msg'ed the guy I got the shocks from about replacement camber plates and here's what info I got.

We do have the upper mounts with new studs pressed in available for the Scion in stock. The price is $100 for the pair plus $15 shipping via USPS. If you would like two (2) new pillowball mounts with bushings add $50 to the total

Anyone could explain what is the pillowball mount and bushing, and why is it separate and should I buy this also ?