I needed to replace the front brakes on my SSBC kit (A153 I think) a couple seasons ago, the pads and rotors were from a 67 Mustang GT, I was able to buy them at the local auto parts store.
I don't know what his kit number was, but he needed 4" lug pattern rotors, and didn't want to re-drill rotors. He figured if he was going to big bolt pattern, he would get the full benefit with the big ball joints.
My point is, and it remains pertinent to the OP's post, is what he needed wasn't readily available. What happens if MBM or Wilwood or Pirate Jack or Ram Man stops offering their proprietary service parts? He could be stuck with expensive scrap.
SSBC screwed over customers, employees, and vendors when they shut down. I believe it would be foolish to think it couldn't happen again, to them or other companies offering similar products.
I'm sincerely happy you were able to get the parts you needed.