Kawachi Fujien Tickets - Can buy at the door?

Can anyone advice if I can buy the tickets at the door? I'm in Japan and I checked both 7-11 and Family Mart and tickets are only avail from Apr 22 onwards.

Please help! Urgent!

I think this page has the answer: http://www.japan-guide.com/e/e4881.html
From April 22 to May 7 only you have to book in advance (due to crowding)

Advance ticket has been on sal since Mach 15 at 7/11 and FamilyMart.

May I know the advance ticket is available in certain 7-11 and Family Mart in Fukuoka only or in any other place like Tokyo as well?

Is the advance ticket a paper ticket or e-ticket?

Advance ticket can be purchased at any 7/11 and FamilyMart throughout the country as long as the shop has ATM like ticket machine. It is paper ticket you are given by convenience store staff. The ticket machine interface is somewhat confusing even if you understand Japanese. In large cities like Tokyo, you'll find a convenience store where Indian or Nepali staff work. Ask them to help you find the ticket category.