I give my two Krill oil which seems to help with their dry skin. Below is where I got it from.
toplinepet.com
When I get too lazy to bathe them or just want a quick in-between bath cleaning, I use waterless shampoo.
Espree
I just saw a dry skin/coat kit but seems to be sold out.... The owner of that store is also a member here who has 4 furbutts of her own. If you have any questions, feel free to ask her. Her ID: mimimomo
Have you spoken with a vet about her dry itchy skin? If it's allergies, allergy med might be needed.