Find out from where you got them how they were wormed if it was by jab they should not need doing again.
If it was by herbal ::)or pellets you could worm them with jabs from the vet this is by far the best way.
Louse powder get from your loacl ag merchant normally in poultry keeping section. If you want to use the internet to buy (why
) you'll have to wait for delivery whilst you piggies go on itching whereas you can go to your ag merchant today/tomorrow unless you live somehwere extremely remote. The internet is good for some stuff but don't think you can get all from it! Bum and off it come to mind.
HTH
mandy