SBMM AX40D Pickups

Hey fellas, I’m a newb on this forum, and I was wondering if you could help me out? Yesterday I ended up purchasing a used Sterling By Music Man AX40 from a local music store used for $250. I noticed before I bought the guitar that the stock bridge pickup had been replaced with a DiMarzio DP100. When I got home and cleaned it up and started looking under the hood, I found out this guitar is actually a AX40D. The neck pup is a stock Axis neck pickup.

What are my options for replacing the bridge pickup? Will Ernie Ball allow me to purchase a OEM bridge pickup if they can verify this is indeed an AX40?
If not, and I have to purchase a different DiMarzio pickup, what pup would be my best choice? Air Zone, Tone Zone, or the AT-1?