Takayama-Hokuriku JR Pass bus reservation

Hi, I am planning on buying the takayama-hokuriku JR pass to travel in early October from kyoto > kanazawa > shirakawago > takayama which includes the nohi bus. I've read on multiple websites that online reservation is not available with this pass and we have to call the nohi bus centre to reserve seats.

The problem is that: 1) We will only have sim card with internet only (calls not included) and 2) staying in an airbnb so can't get receptionist to reserve for us. Has anyone bought this pass and travelled with nohi bus before? Is it possible to reserve seats at kanazawa station and does the bus fill up quickly?

Thanks in advance

Bus reservation is available one month ahead of the departure.
So why don't you call them while you are staying in your country.
You may use public telephone after arrival in Japan, however it is not recommendable since you need tell them your telephone number to book the seats.