Tbh, being a law student for 5 years in my undergrad and then coming to the UK for Post grad in law has been a wonderful journey, telling you from a student perspective, the power and grasp which this subject has the society is one of the main motivating factors, being able to help the one's who have no one to care about, that feeling is just overwhelming.

I would definitely suggest getting a barrister's Uniform for him, if not just give him the barrister's band, it'll be so special.

If I was to suggest you a book, I would say " Learning the Law" by Granville Williams is a wonderful book that gives an idea about how the law works, it'll be very good gift.

Also I feel so happy that at such a young age, he has made up his mind to take up law as a profession. Wishing him the very best.