Here's the deal: We live in East Africa but my husband's family is from Adelaide (I'm American) and we feel very at home there too when we come back to visit, deal with immigration issues, and have babies. We're coming back in 6 weeks. In the past, car seats were hired for us or loaned to us, which was really nice but this time we'll have 3 kids by the end of our stay and we'll be there for 6 months. We use car seats here that I'd love to bring out if possible but I don't know if they are ok for use in Australia. I know there are strict laws (none here in Tanzania).

For our 3.75-year-old: We have a Graco Turbobooster circa 2002. It's a booster seat.
For our 2-year-old: We have a Britax Roundabout also circa 2002. It's an infant-to-toddler seat that can be faced rear or front facing and it has one of those tether straps that I know are required.
For the baby on the way: I think we'll just try to borrow a capsule again.

Does anyone know if these seats would be alright or where I could get a hold of the current safety regulations?

While I'm asking questions, do you think I could fit all 3 of these seats in the back of a car? What do the rest of you do with 3 kids in car seats? We have tentatively been offered a Magna to borrow.

Thanks so much!