While most of the older cameras you have been looking at are perfectly fine, I think a 5D3 would be a much neater fit with your 7D than any of these. It's feature set and layout will be immediately familiar to a 7D shooter. And why not benefit from the most up to date features, sensor, processors, firmware? With the 5D3 prices looking more attractive by the minute, it makes a fairly compelling case for itself.
Also, having owned and worked with all the cameras you've mentioned on a daily basis, I'd reach for the 5D3 over any of them for most of my commercial jobs and personal projects.