Locking handles for T-Slot beds .. need a name for them please :)

[Fivetide]

Ok I need an adjustable handle or low cost quick release for a dual channel T-Slot bed for a project. I've found a picture of what I want but when I search eBay or amazon I cant seem to nail down the actual product name, any one help or suggest a low cost simple way of clamping it into place when its in position on the groves ?

So this is the handle type



and T-Slot extrusion I will use