I don't know about a systemic miticide but there's a few sprays that are excellent but pricey. They are Forbid and Fluromite. They both contain an ovicide so a single application will kill future generations. It also moves through the foliage so both side of the leaves do not need to be treated.

Ortho systemic for roses works pretty good on them. I use the all in one kind with fungicide, miticide and fertilizer. The ones Karyn are talking about are the bomb but cost a lot. I save those for desperate times. I am having a hard time with mealy bugs again so I feel your pain. I spray them and they just move to another plant. I truly hate them and mites and aphids and well never mind, lol.