Hello
If you are the DIY type you can use RG-6 for most of your cable need’s.
RG-6 and RG-6QS is a multi-purpose cable that can be used for composit, component, analog interconnects, digital interconnect, sub-woofer interconnect and s-video
A double run of RG-6 is perfect for long S-Vid runs a little tough to terminate but it can be done. Cost is about $80-130 for 500ft of cable, termination tool
And termination connectors.
If you want pre-terminated cables then Jaxvon's advice is solid