You can get new stocking, maybe the small, inexpensive kind, and put each Rainbow Bridge kitty's name on it with a glitter marker ... That wouldn't cost too much, and you can make new memories to replace the old stuff.
My Great Aunt Bertha said to me ten years ago something that holds true for everyone:

"Start throwing stuff away NOW! Don't wait until you are 80-something and your doctor forbids you to use the stairs more than once a day ..." So you have a head start on some of us, even if it was unintentional, right? Bittersweet ...