If you in the Houston broadcast area, the only legal streaming recourse you could have is using a SlingTV sort of device/service on your existing Root Sports channel from the house. If you are outside of Houston, you could use MLB.TV. If you are in the Houston broadcast area, and do not have SlingTV, you would have to resort to method to illegally stream MLB.TV, such as a VPN or a DNS unblocker.
I go here (make sure you close all ads by hitting "close" or the x button): Spoiler http://www.stream2watch.co/live-now But it's also been less reliable lately.
Hola unblocker also works for MLB TV. Was unaware this was illegal? It seems like a legitimate app on the google chrome store.
Using Hola unblocker is not strictly legal to watch MLB.TV. If you have to use Hola unblocker to watch MLB.TV in the Astros broadcast region, then you are violating the MLB.TV terms of service. And this makes sense - they want you watching Root instead, and specifically, the advertisements on Root that get stripped out when you watch MLB.TV Hola unblocker has another issue as well. The free version turns your computer into part of a botnet. MLB.TV would be within their rights to disable MLB.TV for you if they detect Hola Unblocker. Netflix is already doing this, because enough of their content partners complained.