I think there is no harm in just calling the best tailor you are aware of, asking whether it can be done, and how much it would cost. You may or may not want to mention that it is a PL suit. I'm not sure whether that would raise their estimate. My sense is that the estimate they give you on the phone will be pretty binding on them (not legally, but "morally"). I've heard of people doing this, but I don't know about the success rate, price, etc. The only problem, in my opinion, would be that the shoulder pads may be uniquely fitted to the amount of fabric that there is in the shoulder seam area (or vice versa), such that a new shoulder pad wouldn't look exactly right. But, I'm probably wrong, because I know that others have done this. Look on this board's old posts and you should find some post re: this.