Calling for any help and suggestions about Lice or Mites!

[Nikkipar]

I thought that my chickens were going through a molt, and everyone looks healthy but lo and behold I spent enough time going over them and found ONE little white bug on the one with the most feathers missing. It is too late to go to the feed store tonight... but I will be there first thing in the morning.>.... what should I get or do?????

THANKS!