SwissStop 15s Sintered pads = Impossible to find???

I think they were discounted.

Bit late, but I use the E-bike Swissstop pads in my TRP Spyres. You will burn your rotors long before these pads fade, they're pretty good. One big plus with Swissstop pads is that the lower edge of the pad is slightly ground down, so even though it's the old tall Deore standard the pads will contact modern rotors at the right height. 

Although you can achieve the same thing with any pad if you have a bench grinder or something. 😉