You might try some counter top manufacturers. The sink cut's out are usually smaller. Sometimes when they cut off edges they are a few inches wide and various lengths and are free scraps. They don't have perfect sides but I find they work well for stamping, etc. in leather working and don't weigh as much. Might be something you could find and the weight wouldn't be to heavy for the two wheeled camp carts for hauling to the area you are working in from the parking lot.