I doubt there will be a shop like this tbh. It will maby be the first few loggs, but after that they will give less and less for it. Its your choice, but a risky one! Colo
If your going non-stop to 99 rc you can sell your stuff... I would buy the ess with the runes I craft I think. It may take some time, but buying 10k ess and selling 10k nats and you can craft for a while again, this way you wont have to wait ages for your essence. Colo
To be honest, that won't cut it, seeing as you are starting from only 80 ranged. Get more red chins and prayer potions if you really want 99. Other than that, good luck with 99 ranged! I know, I have some backup stuff banked to buy more stuff