Thumbstick conductive rubber replacement and help.

So for the psp 1000, There's a small piece of conductive rubber to the bottom left of the screen, and to the right of the metal piece that the thumbstick rests on, mine broke and I had to remove it because it kept giving me false inputs, To my surprise i didn't realize how impossible it was to find a replacement for it, I've looked around online everywhere, and all of the ones i can find are tri-coloured white, grey, black blocks that i didn't see in mine, the one i had in my psp was a see-through block with yellow lines running in the middle or at the bottom of it. Can some one please tell me where I might be able to buy the clear ones, or how to install the white, grey, and black one?

I have the original psp 1000. (the fat one.)

ps: the guides on this website don't touch upon anything related to the thumb rubber block, trust me. I've looked.