Stihl Electric Trimmer (Eureka)

I have a used Stihl FSE 60 string trimmer that works but is in need of the AutoCut C 6-2 part (see picture) which I have seen online for $15-20. This is a plug in model, not battery powered. It worked great for a smaller yard but since I have moved to where there a two large yards I require a ridiculously long extension cord so I am moving on to something different!