Here is a listing for an unfinished Taco Concave Longboard Deck

Measures around 38" and 10.25".  More measurements can be seen in the photos.

These are unfinished and/or second hand factory blems at a discounted rate.

None show signs of delamination. 

They may or may not have:

unfinished edges

improperly drilled mounting holes

wheel wells or no wheel wells

or could just be extra from production!