It'll be a bit hard to find new skis for under 500.
May I recommend either the 06-07 Scratch BC WRS (the yellow ones) or the 07-08 Brigades? They're the same ski, and you sound like you need an all mountain fat ski. Especially with it being your first time in pow, you don't want something too fat, and they're 98 in the waist. They're also hella light, they're sick, and pwn switch. You're at a break point between sizes though, which are 178 and 185, so you'll have to choose that.
Other skis may include but are not limited to:
Seth (another good choice)
Line Anthems (maybe too soft)
07 08 works to should i get the armadas jjs
The 08-09 JJs are funky sidecut and rockered. The 07-08s should work too. I'm too lazy and tired to look up dimensions, but they're softer and wider than the BCs, from what I know...I think the waist is around 103...they should work too if you find a good deal.