I ordered 7 EA pieces that were 6LF each. so Roughly 42LF. they are .75" thick and 5.5" wide. Sold as 1x6. I ripped two boards down to 2.75" each and made the frame for the bottom. The top is 5 pieces glued end to end for a total of 27.5" in depth. I traced the shape of the original platform onto a piece of cardboard and just continued the angle of the sides where it met 27.5" on the bardboard. I cut it out and used the bottom of a 5 gallon bucket to get the radius on the two endges. It was pretty easy. I used Titebond III glue and 1" stainless #8 screws counter sunk to screw it all together.

I had roughly 3 feet of a ripped down board left, as well as a few small blocks from trimming the angles on the sides of the platform.