The only part on a 170 that is expensive is the dual mass.
Everytbing else is cheap and there's shit loads of second hand parts about. You can pick a gearbox up for less than 50 and an engine for less than 150 if you look enough.
Type R's are a brilliant car, but for 1500 quid it'd be absolutely shagged. saying that, the only reason I didn't get one was because of all the Ford events I attend