This is the driver used in the SA 314 speaker:
If this is what you need you should be able to find just the driver. Its a Megavox SD-210RX (no threaded nipple).
I bought a SD-210R (threaded nipple) driver from Louis at Strobes-N-More (Sho-Me speaker replacement driver) for approx. $95.00 6 months ago.
The Sho-Me part number for the SD-210RX is 30.0235NT