Right now you can pick up a refurbished T4i for $515 direct from Canon. If you need more power, the 7D can be had for $1074.
I always hear about the poor low light performance of the 7D, how does it compare to the 60D/rebel line low light capabilities.
I use a 550D, which reportedly has slightly better sensor performance than the 7D (see BJP review). The 7D came out first and the 550D and 60D afterwards, so I'd expect the 60D to be similar to the 550D. But if you go to the review of the 60D at DPReview, the section on noise, you can use the little drop-down things to facilitate a direct comparison between all sorts of cameras. Also try DxO Mark. The 550D actually gets a better score than the more recent rebels.
However as pointed out repeatedly on these forums the 7D, 550D, 600D, 650D, 700D, 100D and EOS-M all have pretty much the same sensor and it is probably splitting hairs between them in terms of noise, the differences are more in ergonomics, price, build, fps, configurability, viewfinder etc etc.
Do you anticipate doing other types of shooting (eg sports / nature) in the future apart from just travel? If you don't mind the bulk of a DSLR &/or prefer the broad choice of lenses then that's ok, otherwise consider other small-camera options like the Olympus OM-D, Fuji X100S, Sony RX100, etc etc. But if you really are set on a Canon DSLR and I was in your position I would probably buy either a new 650D or 60D or a 2nd hand 550D, 600D or 60D, use it for your trip and then decide what you want to do when the 70D is released (i.e. probably sell it). It will be cheaper than renting, much better than having no camera at all, you won't lose much money and you'll get a bit of a feel for what you like and don't like about the camera. Good luck!