Where to get new Toto rubber seat screw holders?

Hello - thank you for your excellent forum. I am hoping you can help me. I have a Toto one-piece toilet. My elderly father-in-law brought a toilet seat extender to our house and wanted it installed on the toilet. (It is a piece that elevates the toilet seat by 4 inches). I took off the Toto seat, and noted that the screws went into some black rubbery-looking holes. I did not notice that the screws for the seat extender were somewhat larger than the original Toto screws. After I screwed the new screws in, the seat felt loose. I removed it and found that the black things were no longer there. In fact, I can't find them anywhere. My best guess is that the larger screws pushed them down into the holes in the toilet, although I looked with a flashlight and couldn't see them.

I noticed on another post that you mentioned "rubber drop-in anchors." Is that what these are? If so, is it possible to get replacements? I don't think mine are coming back.

Thank you very much for any advice!

Never mind - as no one responded, I kept searching, and found that these are available at Ira Wood and Guillen. FYI, it is listed as "top mount seat hardware" and comes with the rubber anchor and mounting screws.

Also you can get them from Toto

Click to expand...

The originals are not "lost" but you would have to remove the toilet to recover them.

I'm pretty sure you could find them at the big blue and red box store but you would not find them in the plumbing department. They are in the little plastic pull-out bins in general hardware and fastenings. Don't bother asking any of the clerks because I'm sure they wouldn't have a clue as to what you were asking for.