It's not hard at all. You need Blaster 03+ front spindles and the complete brake system from most any Yamaha sport quad. I think Ken O'Conner racing is selling custom conversion spindles.
I went the blaster 03+ way and it was easy. Just need new hubs, spindles, and of course the calipers, lines and master cylinder. But this was super easy.
They look good for the $200. I would do it. Most of the good condition one are higher price. I got mine for $160 but not that great of condition, but if it works i'm good for now. $200 is a good price