Ankle monitors should be the "default" for enforcing a restraining order, with a lawyer / judge having to approve any exceptions

We already have the satellites and cell towers and the other infrastructure that would be involved for seeing where the monitor thing is.

As for the cost of the equipment itself? Just deduct part of it (or all of it, depending on how much it actually is) from the perpetrator's bank account if he doesn't turn over the amount willingly, in the same way that they might take an unpaid ticket / fine or whatever.