Large Parabolic Panel Reflectors for 10 Ghz EME

I don't understand your question. If the supplier of a 5m dish is going to ship it to you, it's going to be delivered in sections (probably panels). Otherwise it's not going to fit into the truck.

This actually answers my question, So if I choose a 5m or larger antenna I get the Panels.
So which companies are producing professional grade Earth Station Antennas?

Prodelin or Andrew Corp.
I recently purchased a 15 foot diameter reflector from Prodelin and I'm assembling it starting Monday.

The reflecting surfaces is 8 identical sections and each section is made up of a larger part with a smaller section bolted to the outer edge of the larger section (smaller section is 22" long and longer is 68"). You can unbolt this smaller seciton to make a smaller diameter antenna.

f/d =.39

Kch
PS: by the way, to make an efficient reflector, the f/d ratio and the feed beamwidth have to correlate. If you use a small f/d you need a low gain feed and larger f/d needs a higher gain feed antenna to optimize efficiency.