We just went with matching what was already here - 90mm architraves and 140, skirting. It looks in proportion to the doors.
Rosie, how much were you quoted for the doors? I was able to find some almost half the price of the most expensive ones. They are solid but a maple veneer - they were going to be painted anyway.
They were about $250-270 depending upon the size. We also had to have 2 doors made at a joinery and they cost $500 + GST.
We got there here but it does not look like they have what you describe:
http://www.woodworkers.com.au/websit.../edwardian.php
Building and renovating to match original is an expensive task but so worth it. Some new homes have very low skirting, hollow core doors, etc, and it does make a difference to the quality of the finish.