Where can i find a blade for the Challenge Xtreme 33cc petrol trimmer?

hi there im looking for an attatchment for the Challenge Xtreme 33cc petrol trimmer if you need a picture its in the argos catalogoe as a lawnmower and trimmer pack for 199.99. i would like to know if there is a blade that i can put on that is designed for this type of strimmer instead of buying one that dosent fit