Rear leaf spring question

I have a '96 Cherokee Country (4.0 I6, 4x4, 64,000 miles) that's been well taken care of (no offroading or anything extreme...even though it could take it). I have notice that my back end is not as high as it seems that it should. It's been like that every since I purchased it a year ago. My rear leaf springs seem to be fatigued such that the curvature of the leafs is flat - if not somewhat "moon-shaped" down. I looked at them very quickly and there are some kinds of bands that hold the leafs together and I saw at least one of them broken. I cannot tell if any of the leafs are actually that fatigued but I was curious if this something to wory about. I have a class 3 hitch on the back so I'm curious to know if I should replace them to carry the load of a trailer. Also, how difficult is it to replace it on my own? What's a good source for the part (website?, etc.??). If I were to get a replacement, would getting addtional leafs be advantageous since I have a class 3?

Thanks.

Those bands merely hold the leaf packs together during assembly/replacement. Having one broken should not affect anything.

When park on level ground does it look "level" to the eye or does it seem to sag in the rear?

The springs are not hard to replace, assuming the bolts aren't rusted in the bushings. If so, it takes more brute force, than finesse to get them off. Some will use a torch or chisel and simply replace the bolts with new ones (not a bad idea anyway).

Adding a leaf will stiffen them up for use with a trailer but can give you a hard ride when not towing. IMO, better bet is to replace the rear shocks with air shocks. If you tow a load, you can pressure up the shocks to carry the load and level out.

my 1990 cherokee's leaf springs look flat when parked as well. does that mean its time for new ones?

You can have your springs re-arced and add a leaf to them to bring them back to better condition. I've had it done for many older vehicles. Any good spring shop should be able to do the job for you.

The sagging rear is pretty common on the cherokees from what I've seen. I put a 2" lift on my 96 cherokee (less than $150) that added a leaf to the rear, and it brought the back end up nicely and personally I think it rides better now---stiffer in the corners and I get less body roll. BUT many 96 & newer cherokees will get a little vibration even lifting 2".

The idea of air shocks in the back is good, I have a friend who has those and really likes them.

After seeing how thin the sheetmetal is where the shock mount to the chassis, I would never consider air shocks on a Cherokee. I don't think it could handle the weight load of towing anything. I would add a full length leaf (like the Rough Country 3" lift kit uses) or have the springs re-arced.