Yup..I got at least one of these buggers!

Can't be helping the MPG..anyway.
My uncle has had a go at working it and he said it was bloody stiff! Anyways, got it freed up but said the handbrake cable on the right side seems too tight and might not be helping matters? So firstly, how can he adjust this?
Secondly, other than working it to free it up, what else can he try?
Lastly, genuine or non-genuine if it comes down to a new one (is it a case of once they seize its only a matter of time before it happens again?)
cheers