If you have stock suspension, then you should be getting taller numbers for the rear compared to the front. Roughly 1-2". At tire pressure of 45 psi, I'd be really surprised if you actually do get any flat spots.
Definitely get the rear leaf replaced, but what kind of budget might you be thinking? If you like how it rides then don't change it. I get the feeling you want to level it out though?
00 Ram 1-ton ORE; 3" BL; 14" coilovers; ARBs, 37" Toyos; R/T Camshaft; Mopar M1; Custom long arms, sliders and bumpers; 12K Winch; York +5g OBA