Just some legs (or stands) for shelf top, like this Flexi Home Shelf which you can buy easily from bunnings for AU$12

It was designed as small shelf to rise AMS, but since it is beefy it can support heavy duty shelf as well.

Plate 2 is the feet just in case the bottom is warped and not flat.

You'll need 

• 6x M3 threaded brass inserts (OD5)
• 6x M3x25mm screws

I use nano gel tape to glue the stands to the shelf