"If I were" is generally used for things you'll most likely never actually be, like in "if I were you" or "if I were in her shoes". "If I was" doesn't carry such a connatation. In your case, I would go with "was".
Using "were" here makes the clause have a subjunctive mood, which actually means nothing for the future likelihood of the clause, as Chappo mentioned below. Subjunctive mood can give a meaning of wishfulness or possibility, and is used to express various states of unreality, which is different than what I first suggested. "Was", on the other hand, is in indicative mood, which deals with facts and doesn't carry the same possibility of subtext.
In any case, I agree with Jonathan above - don't make it wishful thinking!