Price is for (1) one diaphragm.  If you need more than one, just change the quantity.

This is a high quality aftermarket BMS diaphragm that is identical in sound just like the original diaphragm. 

Outside Diameter: 2.75" (69.85mm)
Voice Coil Diameter:  1.5" (38mm) 
Nominal Impedance:  8 ohms
DCR: 4.5 ohms
Dome Material: Titanium
Voice Coil: Aluminum Wire

Here is a list of the driver part #'s:
4538 and more

to USA （7-15days）