Is it possible to, let's say pay someone money to their paypal account, and in turn they send you a certain amount of toricredits at a certain rate, like 1$-10k?

Yes, it is possible although you have to find someone who is selling it.

Look here

http://forum.toribash.com/showthread.php?t=434948

Yes, check the Item section of the forum.

You may also find useful this link: http://forum.toribash.com/showthread.php?t=429287