The phrase "individual barristers" refers to lawyers who work independently and represent their clients in court. They are not part of a law firm or organization, but rather work on their own. Full definition
I believe the confidence of our profession can in the long run remain high, because you can not keep a good idea down: independent advice and advocacy delivered fearlessly by individual barristers in competition with one another. (newlawjournal.co.uk)
However, because of their cost, these databases are usually beyond the reach of individual barristers, and even sets of chambers find the subscriptions to Westlaw, Justis or Lexis too expensive, and rely on their Inn libraries to subscribe. (slaw.ca)
He has acted for individual barristers and for Heads of Chambers in such disputes. (windsorchambers.com)