You seem to imply having it all prepared for you, and in that case I have no suggestion. Replacing my running
rigging is one of my favorite activities and I do it all myself. The splicing is such a rewarding skill, and the cost is so very much cheaper. It is one of the most unique sailor activities, as opposed to the common boat stuff of fiberglass love and diesel maintenance.
I source my
line from both Fisheries Supply
Fisheries Supply - Marine Supplies Since 1928 here in Seattle, and sometimes an outfit in Bellingham, WA called LFS marine
Marine Hardware, Mustang Survival Gear, Grundens Raingear, Scotty Downriggers & More! - LFS Marine and Outdoor. Both have good prices.