No sources, but why don't you try this.
This is what I do.
I buy
tobacco leaves from farmers or buy ready pipe tobacco. I like Burley, Perique, Danish gold, virginia. I stay away from the English blends, they are stronger and more pungent. Also stay away from LATAKIA tobacco.
Get yourself a gallon of VG (essential depot).
Crumble the leaves or ready pipe tobacco in a boiling pot, add VG until the tobacco is a thick slush...Then bring to a boil....then simmer for 20 minutes.
The end result is a thick black liquid...nearly a paste.
Leave cool overnight. Filter the tobacco from the liquid using a wine cloth. (buy it online).
Add nicotine , and any other flavor you want. (bergamot ...goes perfectly with tobacco flavors.
If the mixture is too viscous, add a little distilled water.
You have a 6 month supply of delicious home made tobacco
juice....Better than anything else out there...
Hope to have shed some light.