a'porth ... Not, I think, a 'Yorkshire' term. In my childhood In East London, (say up to 1938) small amounts of sweets were bought in *a'porths* - probably half an ounce or an ounce in quantity. As most will doubtless know, the word is a shortened form of *half a penny's worth*.
On very special occasions, one might grandly ask *tuppence-worth*. A term of endearment, usually from a mother to a child, was *tuppeny*.