IMO a used Note 3 in good condition is still the best phablet around - great screen, SOC, and battery life. Ideally get a T-mobile version so you get the unlocked bootloader.
The G3 with a 5.5" would have been considered a phablet in the past though it blurs the line now. Unfortunately it's brand new and going to be $650-ish.
I really wanted to like the Z Ultra last year but Sony went too far and made a tablet instead of a phablet. IMO a phablet still lets you pocket the phone and do some one-handed stuff. The Z Ultra basically can't do either - but if you're always going to carry it in a bag or cargo type pants, it might be doable.
HTC One Maxx might be an option as well, though I've never seen any around.