To obtain the Nicotine liquid legally without having to import it yourself and going through the hassle of customs is very easy....
Simply go to a site called "NicoPharm", which is in Australia;
https://www.nicopharm.com.au
You then fill in an online questionnaire, with health details, etc and give your Medicare card details as payment (they bulk bill) for an online consultation with a doctor on the site (takes all of 10 minutes).
You only have to do this once, and once the doctor approves you for Nicotine Liquid it stays on file forever... It's like a presciption with unlimited repeats.
You then get a password to the site and can go to the site as often as you like and place an order for as many bottles of Nicotine Liquid you need (cheaper in bulk).
You also get to choose the Nicotine strength you would prefer.
(I normally buy the 18mg strength and it comes in a 30ml bottle.)
Costs about $10 a bottle.
You can buy flavoured pre-mixed in dozens of flavours or unflavoured.
The doctor then writes a prescription for each order you place online and emails it to their Pharmacy.
Your order is then supplied to your door from the Pharmacy the next working day by Australia Post Express.
The bottles come with the Pharmacy label, address, and doctor's name... Just like prescription drugs you get at a chemist.
A 30ml bottle will last me around 10 days... so about $1 per day.
I prefer to buy my concentrate flavours separately and add it to the Nicotine liquid myself.
Currently, my favourite is the Coca-Cola flavour.