Black-eyed peas: Other than a band, what are black-eyed peas? I've never seen them in the shops but I haven't yet given up hope of finding them in Australia. I replaced them with chickpeas and was very satisfied with the result.
Filé powder: I searched for this extensively online and came to the conclusion that the only way I can get this in Australia is by begging a friend to mail it to me (but see below under Old Bay Seasoning). It is only through the kindness of guma_kawauso and rally_fox that I have any hope of including this, but I know jambalaya isn't authentic without it.
Old Bay Seasoning: This actually is illegal in Australia. Not content to let market forces keep American ingredients out of this country, my nanny state had to go to the trouble of outlawing it. Not wanting to break the law, my only hope was to find a substitute: Bay Seasoning. (In looking this up, I found Gourmet Shopper also stocks filé powder, which I had missed in my searches earlier. Clearly what I said above was incorrect, but my gratitude to Guma and Rally still stands.) EDIT: It seems my information about quarantine may be out of date and you can actually get this by mail order here now.
Vegetarian sausage links: The original recipe called for vegetarian sausage links, but I couldn't insult a jambalaya like that. I'm a great fan of vegetarian cooking, but this kind of ingredient gives it a bad name, affirming the stereotype that you need meat substitutes to have a satisfying meal. In this case though, you can't have a jambalaya without Spanish chorizo sausages. Rats are proudly omnivorous!