I could only pump significant amounts when my babies were newborns, after about the 3 month mark it was almost a waste of time, I think I more benefitted from taking the pressure of my breasts rather than actually producing a decent amount of milk.

I think at 6.5 months (and really, is he 6.5 months already??? ) he would be fine for 5 hour stints. With you out of sight and smell he will likely be content with spoon feeding and water etc and then attack you for BM when you are reunited. DD did this when I went back to work (she was 10m old). She didn't seem to miss the boob and just made up for it with a massive feed when I returned from work, half food/half comfort really. I assume you can work less days if you work longer ones - and this would be beneficial to your little family as they'd have less days without you needing to leave at all