First of, get what you like/what appeals to you, what feels/fits (with adjustable stocks/shims, fit can be tuned to your preferences), within your budget...
Do note that barrel length is less important to one's height/dimensions than is length of pull... and if we're talking about overall lengths, a Benelli with a 28" is going to be as long, if not longer, than a 30" O/U due to the receiver length.
That being said:
$1500-1800 recommendations (new):
Benelli Sport II
Beretta 391 (take your pick - Teknys (most expensive new at 2k), Urika 2, etc)
Beretta A400 Excel (if you don't mind the blue receiver...also available in parallel comb/stepped rib versions with recoil reducing stocks)
There are certain versions of the Browning Citori, and Beretta 686, that can be had for just under 2k (usually field guns)
Now, if you're buying used: 1500-1800 can get you (with some patience and searching)
Beretta 682, 686 variations
Browning Citori Special Sporting Clays
Browning Citori XT
a good number of Beretta 391 variations for around 1k
Last edited by RayPDA; 01-26-2013 at 2:02 PM..