Just replaced mine. I forgot where I had the hint from, I think youtube. Anyway it said order 2x sets of grips so you have 2x 25mm. I bought mine from AliExpress $ 12.- each set.
But I tell you it is not easy ( which you maybe found out already) Left side was not too bad; using a heatgun and very sharp stanley knife and rip it off slowly. The right one I cut through the heater cable which goes into the housing. Could solder them . Before I put the new one on I checked if the heater still works.
Yes, I saw it on youtube...