I don't think there are any ready made sets for your power supply. If indeed there is not, you have two main options.
You can buy a set of extenders, such as those made by Bitfenix for example, and these attach to the end of your current cables. The downsides to these are that they make your cables much longer, so it is a lot more difficult to cable manage. The other main downside is that they don't go all the way to the power supply so you will see standard cables coming out of the PSU, and the sleeved cables going to the components. On the plus side, these are quicker and easier to use than braiding cables yourself, and you don't risk voiding your warranty.
The other option is to braid the cables yourself. There are many guides on how to do this, and you quickly get the hang of it. This option gives a vastly superior result, but it is very time consuming. Whether or not this affects the warranty of the unit is down to the individual manufacturer, I don't know how Seasonic feel about it, so I'd look into it if you're considering this route.
