Look around and see if you have some one that sells Seaboard, That is what I used!
It is made in more colors and is for the food industry. It is the exact same thing and UV protected and use to be 1/2 the cost of Starboard!!
I bought and used a full sheet of 3/4 & 3/8 on my V20. At the time I paided $171 for a 96 X 54 sheet of 3/4, and $86 for a sheet of 3/8.
They don't update there site and it still says the old prices but this is were I got mine. I plan on a full sheet this summer for some stuff on the Sea Ox
http://www.jfreeman.com/cpg_seaboard.html