After he'd convinced you you'd only got one leg – the left – he'd sell you a gross of right-footed shoes. Cheap at half the price! A real bargain. Afterwards, you'd feel you'd been done a favour to, and obligingly walk off with a limp.
refers to something being satisfactorily cheap
Heceleme
refers to some·thing be·ing sat·is·fac·to·ri·ly cheap