Here is one of the wonderful but elusive bass mutes. Attached by double-sided tape. I have just sold my P bass and I don't need it on my acoustic bass.
Easy to fit, very adjustable, switch moves through 4 positions ( unmuted and then three degrees of muting - pretty heavy by pos.4 ). Really easy to use.
Mutes are in perfect condition as is the chrome.
Please let me know if I can help further. More info here although it is not clear if they are still being made: https://www.bassmute.eu/bm_mainframe.html
Thanks for looking.