Blue Dragons are excellent moneyHowever from Alexis's blog

I've camped in waterfiends for these levels as well. It is likely that you can take them out pretty quickly. By RS gold doing Bork every day can help bring in the blue charms. A burst of rock lobsters could be good charms, but I find it to be somewhat of a waste due to the massive money loss the player suffers. Cannoning the more powerful demons of the Forinthry Dungeon can also be a fast source of charms, however I don't exactly how powerful the cannon is in eoc.

I would guess that if you go camping with at waterfiends, you'll be in a position to obtain the charms required to complete 74 by the time the quest becomes available. It is important to make use of your emeralds, spirit rubies and other gems while you're! You may also want to consider doing a mission like While Guthix Sleeps or Blood Runs Deep both of that will provide you with a massive amount of experiences that you can use to summon.

I'd recommend Slayer. Slayer will expose you to numerous creatures, all of which can yield you lots of money, often. From that point on which is your favorite monster to kill.

Blue Dragons are excellent moneyHowever, they require 70 agility them to be effective. In the meantime, you can destroy Black Demons, for money maybe. I would say that the most appropriate gear for you (considering your financial issues) would be:

Melee-Guthan's Equipment (Around 3M, however it does not require food in a melee-able slayer job) The gear of Verac (1.5M and runescape gold 2007 comes with an extra prayer) The ranged version is a good choice. Karil's set. I'm unsure of the price though. It is possible to use Royal D'hide, which is priced at a reasonable cost. MageAhrim's set will cost 1 million. It is possible to upgrade to Ganodermic, which is around 3M.