WTB: Big piece of steel plate

Has anyone got some steel plate laying around? 500mm x 500mm x 8-10mm would be ideal. I’ve priced that up at Scott Metals at $70, which is a bit too much for a fairly small welding table.

I’m currently using a heavily rusted steel BBQ plate that’s been sitting under a pile of leaves for ten years. I went through three flap disks and a grinding disk getting it kinda conductive, but it’s fairly rubbish. I’m currently on the lookout for BBQs by the side of the road, too. Any suggestions?

The metal recyclers opposite yatala pies sell 5mm plate $1/kg. So you could get enough to sandwich and weld together? Good practice for spot welding.