Warpspeed Dyneema by Samson

[Brian Duff]

for low cost (but very safe) workboat style stuff we have been using vectran stay , served over, spliced around stainless thimbles, into galv turnbuckles. Just make sure you buy turnbuckles with a load rating stamped on them, and that it is suitable for your boat. of course making your own deadeyes of wood would be even cheaper i;d think (if the wood was free)

I wouldn't do dyneema with turnbuckles, they don't have enough travel, youd be resplicing all the time...
vectran works fine though