Do not look for any 10" driver to replace the Snell 10." Diameter is just one of MANY operating parameters that matter and the chance that another random 10" driver will reasonably match those other characteristics is close to zero. If the foam edge has deteriorated (the most common problem with age), you need to get that edge replaced, either doing it yourself or having someone do it for you. There are plenty of kits out there, for example, Simply Speakers has a Type A kit for $25 a pair. This is an iconic speaker that still performs very well, so there are plenty of repair options out there.
Good luck.
Good luck.