Swapping out OEM speaker driver with new driver


I have a pair of Vienna Acoustic Mozart Grand speakers and one of the mid base drivers has died.  Any recommendation to swap/ upgrade new driver in both speakers?
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Thanks guys!!  I did hear back from VA and I can get same driver but not matched.  Did find a guy near me in NC to repair the driver so that is the rout we are taking.  The really good news is I found and bout bought a PS Audio Classic 250 yesterday and I am feeling better now jus sayin.  
If you want to send me a good working driver,  I can spec it and find a suitable replacement. If interested,  pm me.  Tim