Didn't figure you really meant that kinda "BEST".

But at least now we have a better feel for what you're looking for.
Take a serious look at the Turkish Huglu guns. CZ and one other outfit I cannot recall the name of right now imports them. They will easily fit within your budget and really are very nice guns. Extremely nice for the price.
There are some Ithaca doubles showing up on the market these days at very attractive prices after they went belly up again. Not sure what all is available but the ones I've seen locally are very nice and not that expensive. I think I've only seen 20s and maybe 12s locally. Not sure if made in 16 or even who the heck made them.
An older American made gun by Stevens, Fox or even the lower priced Winchesters might could be found that fit your budget. There was one locally here for a long time, a Winchester 24 I think it was. Really nice gun for $900 I think and it looked almost new. I sure looked at it a lot of times but being a 16 ga. didn't help it for me. Had it been a 20 I'd have bought it.