Hello! So I was working on replacing the rotors on my 15 IS 350 F Sport RWD last night and I might have messed up bad here. I removed the caliper from the rotor and set it down on a box, but since I was doing other modifications I left it for a bit and worked on those. Like an idiot, I forgot I had taken the caliper off and pumped the brakes a few times because I was checking electrical stuff with the lights. I hear a loud clang and look under the car, and a piston has come clean out of the caliper with brake fluid everywhere. What happened was, when I removed the caliper I had used a flat head screwdriver and it looks like it punctured a hole in the O-Ring looking thing that is between the piston and the brake pad because that had popped off too and there was a hole in it. So I need to get a new one but am getting a lot of conflicting info and need some clarification that's not by Pep-Boys trying to tell me I need a new caliper for $700. The link below is to the part I'm talking about, is it feasible for me to get the part and replace it myself? If so, are these parts universal or do I need to order a Lexus specific part? I know I'll need to reinstall brake fluid, but do I need to bleed the whole system again just to get it to a shop? I was going to get a shop to bleed the brakes for me since I'm, again, no expert and I'm assuming air has been introduced into the system. Again, a lot of conflicting info and I am no expert on brakes. Here's the link to the part I was referencing:

https://www.autozone.com/brakes-and-...E&gclsrc=aw.ds

Tl;dr
Can I replace a brake piston cover by myself and reinsert it back into the caliper? How would I go about doing it and is there Lexus specific parts?

Any and all advice is welcomed thank you!