Hi, I think that you might not quite understand sublimation ink. This changeover process isn't extremely difficult but if you're a beginner I caution trying to do this yourself.
1.) Sublimation ink is water based and is NOT opaque. There is no suck thing as white sublimation ink. You will be installing CMYK ink.
2.) You need SB54 ink. You can get it from multiple places but Calcomp is a great source
https://www.calcompgs.com/Mimaki-Sb54-Dye-Sublimation-Ink-440ml-Cart.
3.) If your print heat doesn't have any problems you do NOT need a new print head. You just need to flush all the solvent ink out first and then switch to sublimation ink. You don't need to change out the ink lines either but I would HIGHLY HIGHLY recommend installing new dampers. Solventinkjet.com is a great source for that as well.
4.) If you do need a new print head because yours is clogged or damaged I would suggest solventinkjet.com
5.) If you are using Rasterlink you can set it to use whichever inkset you want. You just set it to SB54 and this will change the color profiles and settings so that it prints correctly with this new ink.