Nina I will respond to a few of the things you wrote about. I am not a midwife so I can't comment on how easy or difficult it is to get work as a midwife if you are not also a Registered Nurse. However, I can tell you that the University of South Australia (unless they changed it this year) offer the combined Bachelor of Mid/Nursing externally. Also, at UniSA, they subjects studied in the first two years of mid and also in nursing are almost identical in title and content - it is only the final year that is dramatically different.
If you do the combined degree, you will find that the majority of employers want you to have done a Graduate year for both disciplines (nursing and mid) so it may be an option to do nursing, your grad year as a nurse, then apply for post-grad mid and do the mid grad year. The only potential issue with that is how competative mid actually is. Whether you do the combined mid/nursing or do nursing and then post-grad mid, the duration of tertiary study is 4 years both ways.

Karina Good luck with your application. I hope you get in!

MG