Keep those batteries still!
I know it seems like a no brainer to just cobble up a piece of wood to take the place of this one . But its so inexpensive , just go ahead and buy it . It would take you twice as long to make one half as nice . I use it with the battery hold down stud to secure two Optima yellow top batteries . And i really do some serious off roading with mine . You will be more than pleased with this .