What type of 4b do you have?
High lift jacks are quite brutal on the modern day 4x4. As there is a fare bit of plastic and not much places to mount the jack point on.
They realy require strong bullbars and towbars. and to lift the sides which in most cases what you want to lift a chassis that is close to the outer edge.
But i would say that 90-100 is a fair price for one in good order.
neil