What happens on September 9th?
What your dealing with now is only new laws/regulations a state level... after Sept. 9 we have a lot of new regulations going on, on the federal/ national level that will affect every state in the nation.
After Sept. 9, any vape item (whether mods, pods or ejuice) without an application for FDA approval on file with the FDA will no longer legally be able to sell their products in the United States.
The application process is daunting, prohibitively expensive for small businesses/manufacturers and noone still has any clue what the FDA will or will not approve (meaning many will close shop before they spend their life savings on a maybe we'll approve you, or maybe we'll tell you no).
This will crush any small vape manufacturer, (and thus most small vape shops)and much of what is available in the U.S. today, won't be any longer.
Back in 2016 the FDA themselves estimated that up to 90% of what is sold in the U.S. will no longer be able to be after deeming hits, and that date is less than a month away.
Here is a nicotine calculator that will help you to calculate how much nicotine you'll need for stocking up.
Vaping Community e-liquid Calculator - Vapocalypse Calculator
And so you know, we decant our nicotine into glass bottles, wrap them in bubble wrap etc and store them in the freezer. This way they will keep for a very long time to come. (Many have small dedicated nicotine freezers, that lock. They aren't prohibitively expensive and this keeps nicotine away from food or any potential accidents, although not everyone goes that route.)
Also, the most common nicotine base to buy is 100mg/ml... and for freebase nicotine it's running about 50 dollars a liter (1000 ml)...
our lawmakers would like to add a per mg nicotine tax at the federal level, which if successful, would make that 50 dollar bottle of today's nicotine into nearly a 3 thousand dollar bottle.
Not trying to scare you... it is what it is though and you should be thanking Maine in some degree because at least you know now. The governments angry about the loss in tax revenue by everyone quitting smoking... and they are going to try to either destroy us, or tax us the same as cigarettes so they aren't out any revenue.
Like someone else said, your best bet right now is to find freinds or family in a different state so you'll have a fighting chance.