Icing sugar and 'sugar rolling' the bees in it might be yet another alternative (no VMD on icing sugar yet?) to spending out on 'ApiPoxall' (as icanhopit calls it). Just need a funnel to shake bees into the 'sugar rolling' box, then run them back into the hive. Culling the first capped brood would/should mop up almost all remaining mites.
Not a sensible option for multiple hives, maybe. Time consuming and needing good timing and conditions after the shook swarm.
Just thrown in to save people being fleeced by the extortionate 'ApiPoxall' mob without falling foul of the law. Not done it myself, for several years, but it does work. This is not to be confused with 'sugar dusting', of course.