If it is your first time sleeving, I suggest buying extensions and getting a feel for things - you don't want to break/damage your power supply.
I started off by buying some extensions, sleeving, and heat shrink off eBay. The extensions were poorly made but it turned out to be awesome because the pins came out really easily. A buddy of mine bought those n-gear ones from NCIX and ended up breaking a bunch of pins because they wouldn't come out of their hole (using both the staple technique and the sunbeam tool).
I bought
this sleeving, and my buddy tired
this and they both look great.
I just put in an order for 200 feet of neon green - comes to ~$30 after shipping to sleeve another power supply.
Anyway, good luck