We used flooring from Homedepot for the middle boards.  My decorator suggested that I make it longer and that worked well with this flooring.  We did discover that our Lowe's has the post for only $10 - we paid too much at 84 lumber - only to discover that they were warped - we had to use corner brackets to fix it.

Homedepot - Maui Whitewashed Oak 8 mm Thick x 11-1/2 in. Wide x 46-1/2in. Length Click Lock Laminate Flooring (22.28 sq. ft. / case)