This one can be bought in the U.S. right now! No idea if this is a legit outfit. If you buy one, let us know!

Features:
Current settings from 0.5 to 2mA in 0.1mA increments.
Duration up to 30 minutes with countdown clock display.
Continuous monitoring and display of actual current.
Continuous monitoring and display of electrode quality.
Slow ramp up for skin conditioning and comfort.
Automatic abort on excessive resistance to prevent skin irritation.
To learn more about tDCS, visit the how it works or the research section.

via TCT Products | Easy to use, precise and safe transcranial stimulators for tDCS applications.