I'd also avoid Indian... I always apply the rule of "if its a country in which I wouldn't drink the water, I won't shoot the ammo either..." While it may work for some, for how much M1A's cost, I'd hate to have a Ka-Boom.
Port can be had from the Ammunitionstore.com, as thats the one place locally that I've gotten a few cans from.
Aussie has been more and more difficult for me to find locally, however there is a lot of argentine mfg'd aussie contract ammo which has turned up for a decent price.
Also I think Kyimports.com has some Santa Barbara ammo which is quite good as well.
And, for what its worth, I've been seeing some Malayasian .308 turning up locally, I'm not sure where its coming from but I'm getting it when I see it.
I'd also check out South African. While its not as good as port or aussie, my Fulton rack grade really likes it (With the cold weather I've only got access to an indoor range locally, but the target was shot with 20rds of SA with iron sights the other day) Aimsurplus has it for about $154ish for 950+ rounds.