Using HttpService to get a list of a players friends?

So recently I've been messing around with HttpService's GetAsync method to do things like get the # of followers an account has on twitter and things of that nature. Now I'm interested in getting a list of a players friends. Now the only problem is that it only loads the first page of friends with the url of http://rproxy.pw/Friends.aspx?UserID=[USERID]. So my question is: Is there a way to load another page of friends by using another url or even better making it display every friend on one page. Or maybe even somehow using PostAsync to get a list of the friends?