If u haven't got a lot of money, go for a small one off a 1.1 or 1.3 fiesta or something - can get em exchange for about 35 quid.
As the RST is low compression, its easy to turn. Becasue the motor is smaller, its much less effected by heat. Mine has never failed or hesitated, where as the larger type did.
If u want to spend 100 quid or so, goto Ford. It's a totally different design of starter they use now, they spin the engine v quickly, and sound really nice too.
Rick.