We have silkies who are prone to getting scaly leg mites. We've been through them three times now.
The first time: Mixed Vaseline with some Desitin diaper rash and Vicks. Brought a flashlight and a partner and at night, slathered their legs and feet with it. Skip a night, third night do it again, skip a night, then do it again for 3X total. That took care of it.
The second time: Same thing.
The third time: We had 14 silkies this time and no way I was going to slather 28 feathered feet, so I went the Ivermectin route. Per
https://bitchinchickens.com/2019/04/29/ivermectin-for-parasite-control/ we used one drop of the 5mg liquid Ivermectin on their backs up toward the neck and spread their feathers so it hit the skin. We repeated it in 10 days. This was about a month ago. They are looking way better!