The 724 is the FEL that comes with the L4600 tractor. Yes, it will lift over a ton at the pivot points. I do not know if it will fit a 3200/3800 tractor.
Frankly, you can be getting into serious trouble going for more lift. Most of us with 3200/3800 tractors are putting a whole lot of ballast in the rear, to counter what the 524 loader can lift. Adding another 500 lbs in the loader bucket can have you on your nose.
My dealer said Kubota rates its front axle for about 2600 lbs - I forgot to write down the number, so I can't guarantee it. That number is also about what R1 tires will handle, depending on the ply rating. The weight of the loader, and its load, are effectively doubled on the front axle, because their center of gravity is well out in front of the axle. The weight of the 524 loader with bucket is about 1150 lbs so it alone gets you to the front axle rating.
I wouldn't want to go for bigger and heavier, without also getting the bigger tractor to handle it.