These are my own magnetic paddle shifters for sim racing, the hardware needed is
Pretty simple but very functional design, I personally like the feel and they work like a charm
I mounted my paddles with another couple of M3 nuts and bolts, just pick whatever paddles you like or design your own!
(just a little tip, don't go with very big/heavy paddles or they'll take away a lot of the clicky feel)
The author marked this model as their own original creation.