please help slave cylinder problem
 

hi guys my 2.5td w reg voyager stopped going into gear i have noticed that the slave cylinder plastic on the front bit has snapped,would i need to replace the slave only or master & slave cylinder,need help asap as i rely on my car for school runs etc and dont have a much idea on these vehicles,iv had problems getting it into 1st & 2nd gear for the last year.

kind regards

kay