I was also prepared to head up north, however have heard from a couple of mates that have been in Darwin and Far North QLD for the past coulple of months, jobs are scarce and experience required is high.
Well, first thing's first, LOOK AT THE BIGGER PICTURE!
"Up North" covers a hell of a large area, and for someone with your sort of experience, Darwin and FNQ are pretty well out of reach until you've done at least a year of charter/scenics elsewhere (i.e. 500hrs plus). There are some exceptions to this of course, like the Aboriginal community basings in Arnhem Land that many Darwin companies will send you to with low time.
Do a bit of research and you'll find many other places which hire guys with your sort of time. I'm one of 6 guys I know who "went north" this year, all with between 220 and 360hrs. 5 of us now have jobs, and the only reason the other bloke missed out is that he's in Darwin. Draw your own conclusions.
As for what to do now, well that's a toughie. You've left your run a little too late this year, so start aiming to head up here Late Feb/Early March next year. Until then, I would suggest knocking over the Instrument Rating and finish off that AGK subject (you'll find it very hard to come back to later once you're flying your a**e off). Find some meatbombing work to keep you occupied between now and when u come up, and get yourself that extra 100hrs or so that will give you a slight advantage when it comes to employment time. Find another non-flying job and start saving! You'll need those funds when you're hanging around up here waiting for any sort of work.
OR Do an instructor rating, find some casual work and also get those extra hours to make you more employable. 250hrs vs 350hrs doesn't sound much, but it is in the eyes of some employers.
I would go the first option, for two reasons. Firstly, it gets the Instrument Rating out of the way and on your way to your first renewal (X number of renewals forms the basis of many companies employment requirements). Secondly, if you find some meatbombing work you'll most likely be flying the larger Cessna types which you'll almost certainly be flying once up here. Time on type is also a slight advantage.
Heaps of people who read these forums will be able to help you out, but it's up to you now to do some research, put out some feelers and make a decision.
All the best.
TL