Recommendations For A Solar PTZ Camera Supported By Milestone?

Not exactly sure what you're asking for i.e. are you wanting a PTZ camera with a solar controller built into it or just a PTZ that can receive power from a solar array?  If its the latter, the answer is:  any PTZ listed on Milestones supported hardware can be used.  All you're doing to make it "solar" is adding a solar controller, solar panels and batteries to the pole/building.  The transmission method i.e. cellular/wifi has nothing to do with the solar power other than, if those devices also need to be powered by the solar, you'll need to do the correct calculations of power draw under load to ensure you have the right type and quantity of panels and controller.  I will caution you that although this sounds super simple, and it is really, there are things you need to understand and make sure are part of your design or you're going to be losing power often.  Example:  direction and tilt of panels is critical and not the same for every application, some solar controllers won't allow you to remotely monitor its health and this is very important to have if you're putting them out remotely, there are various battery chemistry's like lead acid, gel cell, lithium and the kind you choose will impact reliability and serviceability. I'll be happy to discuss this with you in more detail as we just spent 5 years learning the lessons painfully and now have a solid working system.  I can share with you what I know and direct you to the suppliers we use who helped us through the learning curve.  Look me up on LinkedIn.