Britsh Honduras was a British Colony that is now the independent nation called Belize. It was 1st ruled by Spaniards and became British Crown Colony from 1862-1964, when it became it self governing. It 1981 it was granted independence from UK and was called Belize.
I bought this stamp sheet also in Leicester, few weeks prior to my return to Malaysia. I hope someone can shed some light on when it was issued to me.
PS: I believe it to be 1938 but am not certain.