That's just about impossible with no stats needed. I'd say the best one I know of though is usfine. Sure, it'll take them like 12 hours for 5M, but they're efficient enough to actually not scam you but get it done in a certain amount of time.
US fine would be the best for that although i think depending on your stats they might use a transfer method instead of farming the gold. Don't they have two sections on the website one for gold farming and one for Rs gold?