I see a rating requirement of 2000. that means my gladiator would need a rating of 2000 at that point in time correct? So far only Bruce, The Returned and Razael have made it above 1400 rating, so that's going to take a long time, especially if you must have a rating over that point at the moment you are making the purchase.
If the item has a ranking req. on it then you'll need to have that or greater to buy the item. If you drop after that it is still yours and usable.

I also see on our gladiator's overview page, that glads now have BGP: X/8500. I assume 8500 is the most amount of points you have have stored at any one time and purchases in the chamber of power get removed from that total.
Correct.

Last thing to comment on, is why am I seeing epic 1H weapons with damage per round of 480-580 but no 2H weapons above 500?
The DPR calculation is an estimate based on the low and the high damage and the speed of the weapon (in a vacuum). Your strategy alone can shift those numbers up or down easily since DPR is Damage Per Round and if you stand there doing nothing your DPR will be 0. I'm sure your 2H weapon will do more than 500 damage.

Good luck in the Pit!

-Nate-