I spoke with Thomas last week, my grip is an older model, it will fit only the K10 and K58, the latest version will fit more models.
I ordered a replacement grip and apparently it will fit my K58 and also K12, K10, K2, K2s, K60
My original Rink grip is made from two pieces of wood so it looks like the rout was made and then joined together.
Hope these help, if you need anything else just ask