Here in the US. HPI x-patterns can be had from almost any online retailer.

The 24mm Ride tires listed above are excellent. Low side wall, good grip, long lasting. The only thing about them is that they are small wheels. Width and height wise.

The 26mm Ride tires I have recently tried. They are just as good as the 24mm. Good quality. They have a higher side wall and wider width. I recommend all of the tires mentioned.