As a U.S. citizen attending a U.S. school, I believe you're eligible for federal financial aid even if you live abroad. But talk to Penn Foster's people for this to be sure. The other thing I would do is make sure ahead of time that a nationally accredited Associate's degree from the U.S. will actually qualify you to work in a British pharmacy.
-=Steve=-
B.S., Info Sys, Charter Oak State College
M.A., Educational Tech Leadership, George Washington University
Doctor of Health Education, A.T. Still University, in progress