My clutch just went 10 days ago, doing the same thing in 5th gear and also juddering heavy on pulling away from a standstill with any slight incline of the road!
After taking advice and knowing the facts that I enjoy 1/4 mile dragging, my only option was to go for a twin plate. I bought the Exedy twin plate Compe D from RHDjapan for £800 delivered.
I guess if 1/4 mile action isn`t your thing then an uprated single plate would do and cost less than £300 + fitting.