I'm not an expert, but generally, I don't think class standing matters quite as much in the west. The best thing to do is to ask around on your campus.
I wouldn't think that rushing as a sophomore would hurt you're chances as much as being a junior anywhere.
Go for it. As an international student, you'll be very memorable and I think as a soph you would stand a good chance at U of A. Good luck-- give it a shot!
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