Clamp & articulating arm suggest for overhead photography rig

I’m in the process of building an overhead photography rig for food photography

I’ve got a single horizontal metal bar going across the long length of the table with the idea of clamping something similar to this on it with my camera hanging down. The problem I’m having is that I’m unable to find anyone who sells something similar to this Neewwer articulating arm which would take the weight/work with a ballhead, Nikon camera + lens (around 1.5kg total)

Does anyone have any other suggestions or know a brand which does this?

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