Most of the old raids gold loot got nerfed pretty hard, so this is what each raid will give you. Did this solo with a prot pally, around 810 ilvl. This will help you decide if you want to run each toon through solo or as a group.

Times include travel time and I did each raid back to back. I'll edit as I complete more. The gold+loot is what you get after selling all the items that drop off the bosses as well as the actual gold. So running these 5 raids gave me 4425g total.

RAID - GOLD - GOLD+LOOT - TIME
Dragon Soul 25H 6 Bosses
426 1051 0:20
Firelands 25H
494 1417 0:18
Blackwing Descent 25H
470 961 0:13
Bastion of Twilight 25H
375 769 0:13
Throne of the Four Winds
135 227 0:09