JK88
Since your bankroll is small you are in a good position to just back the NRL specials from the sportsbooks and have a huge edge, in my opinion you because can't lose. Make sure you look at the online books and take advantage of the promotions.
When you sign up at a new book make a big deposit and get the bonus bets that come with it, since your bankroll is small sign up at multiple books and receive multiple bonuses, place one bonus from a sportsbook on one side (line betting or totals) and at an alternative book place a bonus on the other side. Free bankroll booster, it's even better if you can find a nice middle and you might be lucky enough to win on both sides.
When you get even money on a short price ML fav like that $50 Waterhouse promotion always bet the max limit, you can have something on the underdog also to ensure you win regardless of the result.
Basically, I'm saying that small bankrolls don't have to beat the handicapper to win.