Ok, I think I've overcomplicated things here, so I'll try to make this as streamlined as possible:
1. To minimize my risk a little, I'll send a very accredited and trustworthy member here two bitcoin installments of $250.
2. You will deposit $250 into two paypal accounts. I will send off the second $250 bitcoin payment when your first payment has been verified.
Boom, problem solved. (And really, the only person risking anything here is me.) You're not going to find a better deal than that, especially in Afghanistan.