Steve, I don't think we are in the same club, I'm at SASI, but I also do as you have indicated. EQ6 in a hard shell suitcase. I went to the local Westfield and into one of the luggage shops with my dimensions of the mount and found a nice size case, which was on special at the time too.
Next trip was to Clark Rubber with a template of what I had in mind and the nice guy there said no worries bring the suitcase and bits and pieces in and we will cut it to fit. Exactly what he did, I now have the mount, hand controller, spirit level, tube rings for my ED80 in the foam and I can fit the leads and accessory tray in a plastic shopping bag on top with some foam between to make it all cosy. It works a treat but the suitcase is mighty heavy with the EQ6 in it - good exercise though

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White Rabbit, my brother in-law has a HEQ5 and he took the original foam packaging and built a wooden box to put the foam in to cart the HEQ5 around. It also works a treat and is an alternative for you if wanted to do a DIY project.
A couple of options for you to consider.