D-punch/die set for SMA panel cut-out
I'm wondering if anything like this even exists ? Has anybody heard of
anything that may be used for cutting out SMA coaxial holes into thin
panels ?

Try Duratool: -

Also available from CTC, Greenlee and quite possibly several other sources.
It does look like Greenlee do these punches: -

It may be that this is the very one you seek: -

Available from here with the part number being Greenlee # 60077.