Vintage speakers very, very rarely( especially given our working environment) retain original cones. Even if unused, the cones deteriorate significantly. This is true of Altecs, Tannoys or any other make. Altec alnico magnets can be remagnetized-Sidewinder for example offers this service.
Even amps rarely make it through many decades of (mis)use without getting scarred. I am currently restoring a pair of Klangfilm amps. monoblock EL 34, rescued from the scrap heap, that I was fortunate enough to stumble across. These have seen better days and the restoration process is hugely assisted by the amount of information available on the net. Klangfilm(German for Sound and Cinema) was Siemens Germany's cinema equipment label back in the day.
There is a lot of learning that one goes through during a restoration/vintage project, some of which is relevant for future projects, and some unique to that project. Patience and ample time are required, as well as other standby systems that you can use in the interim. It's akin to a vintage car restoration project-which I've seen at close quarters, but not done. For example, Altec refurb kits are available through GPA Audio or Hunter Audio, and many other vintage gear refurb kits are also available, though at a price-Lockwood Audio for example supplies Tannoy spares. Klangfilm parts aren't easily available, though.
So in answer to your original point. for us in India, getting hold of NOS gear in pristine condition is near impossible.