Aluminum Extrusions for Spoilboard

Does anyone know what are the widest aluminum extrusions available and where to get them? I want to replace my MDF Spoilboard with aluminum extrusions and MDF sections but have only seen them 375 in width. I wanted to know if anyone has seen wider extrusions on the market. Thanks everyone for your help.


Misumi has 1000 mm by 250 mm so with four of these you can cover your 1000x1000 x carve.