Here's the cover.
After having the cover you will more than likely have to build the pickups from other parts.
You could use parts for a emg 35 or 30 pickups
Ceramics work great for bass.
mount the bobbins and magnet to a home cut plastic baseplate, with super glue.
Attach the cover with wax potting.
You have to figure out all the particulars, and best way to mount.
I've not made TBird pickups, but I've made lots of other bass pickups with similar techniques.
Don't overwind for bass, or you get mud.
Anyone else have ideas, please jump in!