As luck would have it, "pork" and "talk" are rhymed in the first verse of Ian Dury's superb song This Is What We Find. I suspect the rest of the lyrics will only add to your confusion, unfortunately.
My Canadian ear somehow corrects the "pork" and "talk" so that they still don't quite rhyme (though they're certainly close enough for slant rhyme)
I hear the "r" in pork even if it's less audible than it would be in my English. And the "a" in talk sounds a little more like the "a" I'm familiar with from talk than the "o" in pork does.
https://www.youtube.com/watch?v=QKoh1J84uCU