You could get a set of the slightly taller 99 model rear springs. Or for a more budget choice the moog equivalent. Should be able to find part numbers here pretty easily.
The ome 2906 will poke the rear up quite a bit if the front is staying as it is now.
That's a good idea if you are going to have a highly variable load (regularly towing, for example).You could get OEM 99 rear springs + airbags and adjust them in accordance to your load at the time
OEM 5th gen springs would be your best bet. 1"-2" of lift (depending on your current sag) and noticeably stiffer. Also cheap!
They are slightly bigger in diameter and will be a touch loose in the spring seats at full droop, but will work just fine.
OEM or aftermarket "99 Tall" springs will also work, but won't handle extra weight well - which may or may not work for you.
-Charlie
They are fine when flexing, just loose at max droop (jumping or putting on a lift). I run 10mm trim packers with mine for a touch of extra lift and to keep them snug at full droop.I'm running the 5th Gen springs on the Rear of my 3rd Gen. They work great, and I was definitely maxing flex this weekend with no issues!