I'm looking to learn from someone who is 7th Dan or higher and am willing to invest 1 to 2 years full time anywhere in the world.
To get the first 111 "7th Dan or higher" look her:
If that's not enough I have at least one more (not listed) who is the sensei of my dojo-cho.
Ask if they have an ushi-deshi program.
The rest of the answer to your question will hopefully be done by someone else