Drivers for Broadcom 57xx on Lenovo

Okay, my customer just received a batch of Lenovo Thinkcentre A55
machines which have a Broadcom NetXtreme 57xx NIC.

Surprise, surprise, their ZDM 7 sp1 network doesn't have drivers for it!!

I've looked on Broadcom's site and the only drivers they have for linux
are server drivers. How can I go about getting a zen 7.0.1 initrd which
HAS these drivers in it, rather than going through the nonsense of
opening it up on linux, etc, etc, etc, etc?

Please? Anyone?