For safety's sake, pick texts that are about, or were composed, in the 19th century - your well contstructed rationale won't be immediately apparent to a marker, especially if it doesn't really come into your essay. Don't make things harder than they already are.
Texts from other countries are fine, and, in fact an excellent idea - my class was encouraged to look at places other than England - For supplementaries, I used 'J'Accuse' - an open letter by Emile Zola, published in a major French newspaper in the very early 19th century, and Geraldine Brooks' 'March' - which tells the story of the father from Little Women's experience in the American Civil War.
By moving outside of England, you get a broader perspective of the driving forces of the 19th Century - a lot of the uncertainty in England arose from instability in France, America and Russia. Additionally, looking at literature from British colonies (including Australia) offers an excellent opportunity to contrast various individual experiences.
Try to find a text that takes a male perspective, as well. Individual and Society isn't all about repressed women. Lots of people got a pretty raw deal in those 100 years, and looking at industrialisation, religious tension and racial tension makes the unit much more interesting.
