You can do heroic Gundrak in shiny greens.

There are a ton of upgrades in that heroic alone for a newly minted 80 team and it gives you 2100 rep along with 5 emblems per run. Takes no more than 60 to 90 minutes for the non-overgeared.

I didn't leave there until I had some gear, but my few runs of heroic UK lead me to believe that could get on farm status pretty quickly for a new 80's team as well. More upgrades.

So, between rep being generated on ALL FIVE toons concurrently, drops, and emblems its a pretty fast and predicable way to gear up at 80.