Not a centre finder, but this style work quite well.
https://www.aliexpress.com/item/4000...700002904316_7
Attach it seperate to the spindle and use tool offsets to put it in position.
This worked well on my plasma cutter but positioning did not need to be precise.
For in spindle high precision probe, something like this.
https://www.aliexpress.com/item/1005...apt=4itemAdapt