From excellent Rollerblade customer service, I learned that all replacement pads fit all inline models.
In stores on site I was not looking for, but he got from Rollerblade the link that I found this brake-pads. They were delivered promptly, adjust, assembly was not a problem. The block brakes super. If he has left again, we have another in reserve. And if that is also worn, we know where we get new ones. :-)