Buy online tickets Ferry Wakkanai Rebun

We are thinking of going to Rebun in August 2016 and I would like to know if I can buy the tickets online as I don't find that option on the internete. Thanks

For Japanese (input by Japanese) web form exist but no ENG web form.

Booking(for 1st class and Special room) starts just 2 month before from dep date.
Call ASAP if need.
http://www.heartlandferry.jp/about_yoyaku.html
URL copy to Google translate.

http://www.heartlandferry.jp/english/index2-2.html
ECONOMY CLASS(2nd class/cheapest) : no booking system but need bording procedure until 30-40 min before like airport.

http://www.heartlandferry.jp/rishiri/ship.html
1st class : 1等
Special room :　特別室 (20000Y/6 passengers max)
ECONOMY CLASS(2nd class/cheapest)　: 2等

Thanks.

And to pass the car to Rebun? What can I have to do???? Thanks a lot.

What is ASAP? I do not know how to buy the tickets on line.

ASAP means 'as soon as possible'
I am also looking to book tickets for ferry across to Rebun and Rishiri