How many firebricks for a 6 inch system?

I have a bunch of firebricks, planning to sell some, but want to make sure I have enough left for a 6 inch system.
I want to make the whole J out of them including the riser.
Have Ianto et al's book and Paul's dvd'.
I forget if the book has description of how many and I haven't had time to watch Paul's dvd's.
The firebricks are size about 2.24x4.5x9 inches.
Thanks, I will check Ianto's book tonight also.
Searched this forum and also through google, couldn't find an answer except one that said 67, but I assumed that was for the feeder and burn tunnel, not the riser.
Maybe I'm wrong.

Hi; Build a mockup of your stove and riser, this is the only way to see just how many bricks you will need. Good luck Tom

there's a materials list for red brick (firebrick's a bit bigger, so you might have extra) in our daybed 6" plans.
they go for $20 on our website,
or for not much more, you can get the same plans plus a bunch of other great stuff* as part of the Everything Combo; Ernie and Erica Everything Combo

I may also be putting the brick diagrams on the cover of our new book, so you could count them (look at the post from earlier this month, Sep. 2013): http://ErnieAndErica.blogspot.com
The diagrams with the brick box around them are from the 6" plans; the ones without are from an 8" plan, but there is no way you would need more bricks for a 6". Don't forget to add up the duplicate courses of the heat riser.

(*the great stuff includes our Art of Fire booklet, the RMH Owner Manual (which Ernie calls the "baby book" for recording your stove details, plus routine operating instructions), and many plan sets with buildable scale drawings and materials lists for example heaters that work great in their setting.

-Erica W