I upgraded my S9 with the S10 laser head and linear rails and coulnd't find any working holder, so I designed them by my own. I used the red RepRap endstops see in the last picture.

For the Y-endstop I made a bracket holder in 2 versions, either using a M5 nut or one of the spare rail-nuts from the laser itself.

You need aditionally 2x M3x10 or M3x8 screws to mount them.