Olaf,
I'll bet I am the only other guy on this site that has been to Wakkanai! I was there in January 1983 and it was colder than a brass monkey! Our train stopped in Ottoineppu to pick up a car and it took the crew 30 minutes with a propane torch to thaw the coupler enough to couple the car to the train. I was living in Nayoro at the time. Though not on the Asahikawa - Wakkanai line, I bought this keychain depicting the Shimokawa station sign and a lantern. I was serving as a Mormon missionary at the time and traveled all over Hokkaido by train. It's neat to know someone else on this forum has been there. I'll dig up some of my railroad slides and post them!
Gordon