Far too many other jobs I need to do than add an other oneOK,may as well throw in the option,"make one" perhaps?
I had them cut a top for me, to fit a frame I already had. Works well.Try these guys
I bought a top from them and made my own
They say heavy duty, I would suggest 5mm is not that. maybe I’ll have a look at producing a heavy plate with slots in that regular clamps can be used in and also the edge.can be used.