Well good luck on that one
It's a tough job on slots but a strategy of some sort is good. I have one that I use but no guarantees. Assuming you are going to play Microgaming slots, go for a free spins slot less lines (probably 9) like Thunderstruck or a low/medium variance slot with potentially good bonus rounds (Avalon and Kathmandu) and use an incremental strategy maybe along the lines of
the one I use.
I'd probably avoid
RTG slots as bonuses come round less often, are less predictable and some
RTG's have a max $4k cashout limit. But thats just personal choice.
Another advantage of MG slots is the volume of denominations you can wager at. I would have suggested "Thor" on Cryptologic (Intercasino) but the jump in bet size is too big for what you want to do. "Cleopatra" (Wagerworks) slot at Virgin is ok but it's 15 lines so reaching your target will be tougher unless you play it at 9 lines. You'd probably be better off going for the "50,000 Pyramid" on the same software as bonus rounds tend to be more frequent with good potential. But the wins imbetween bonus rounds are smaller.
For this, personally, I'd use the MG slots I mention above with the incremental strategy, probably starting at $6.75 a spin and working up ($9, $11.25, $13.50 etc) or down from there based on bonus frequency (see strategy). Another key is to keep cashing out as you go!