.308, most modern .308 can out perform 30.06, in all but the hottest hand loads. More rifles of all types are available in .308 semi auto, bolt guns, lever guns, etc. Unless you plan on getting an M1 Garand (there are Navy contact .308 Garands out there too), I'd look at a more modern round.

Also during an ammo shortage, most manufacturers will be pumping out only their most popular rounds, .223, .308, etc. 30.06 is no longer one of these. The 30.06 had it's time, but when NATO adopted the .308, the die was cast. Current stocks of surplus 30.06 are pretty much depleted, like the Greek HXP, and more will not be produced.

The 30.06 will always still be around, but it will eventually become an elderly cartridge, that few people will still chamber except for collecting and enthusiasts.