With the 24in depth, I suggest you only look at high intensity LED's (such as those Kessil uses in their light fixtures) - maybe chat with BML (Build My LED), when I discussed my tank with them, they suggested I just go with a couple of locally available options re fixture cost + import + shipping pushed their own units well above the price of the Kessils I was considering.
I doubt you'll find sufficient intensity/even coverage lighting without going to the upper limits of your budget, or even slightly beyond once you add in hanging kits & controllers (shop lightly used if you can)
BML has an introduction to LED tutorial/video that is worth watching (it's available on the MACNA site, or BML may have a direct link now???)
(eg, Kessil A360W-E Tuna Sun is considered to cover a 24" square with 36" penetration - you'll likely want to start at rather lower than 100% intensity)