Hey mang,
If you have the original woofer reconed (if that's possible), 50% or more of the value for the pair will vaporize. The same goes for a modern replacement. I would suggest you pay the small fee to become a member here and post a wanted to buy ad on Barter Town Parts for a vintage replacement. There's also the online auction site that everyone refuses to write down the proper name of.
I restored a pair of AR-4X's. Both my woofers ended up being trashed, and I ended up having to purchase 3 or 4 replacement woofers off epay, can't remember why so many. Apparently, there are approximately 3 different versions of the same woofer. I listened to all 3. There was no discernible sonic difference that my ear could tell.
Biggles