Good luck, lately I have found Verizon reps to be less helpful than in the past... I dunno, maybe it's just me.
But in any case, I highly doubt they would or even could send just a back cover, but Amazon has people selling 'em for like $4.00. Not too shabby if i do say so myself.
But either way, the replacement's letters are just gonna peel off too. So keep the one you have now, but just let the other letters peel off/peel them off yourself. I've heard people mostly like that better- looks cooler.
I use a Seidio 3500mAh extended battery+ cover, so I have never experienced this issue, but it's all over the internet haha.