Brother i have same model of Mehran,. And i had same issue of bearings many time. I replaced as per different mechanic suggestions' but every 3 or 4 month problem again rises. Sound like "Wonnnnnnngunnnnnnngoooooo" comes from bearings and increases on high speed.
Before i used different chines brand ( 2x 250/- each tyre) plus mechanic cost. But after fed up i preferred Japanese brand (although am not sure its original Japanese) MItsubshi.(2X650/ each tyre). Now almost 8 months i dint face any problem.
One big point i experienced is always go to some expert mechanic having all tools of this kind of job. Caz i observed many laymans having nothing and want to put bearing by hammer and chisel which will ruin your wheel hub and cone.
