There are several organized militias in Texas; you can search for info on joining--all have armed divisions. I believe Texas also has its on militia.

Abbott has the authority to use militias per the 10th Amendment; however, at the rate he's going he'll probably try the Boy Scouts, maybe even the Girl Scouts, first.

"California, Arizona, New Mexico, and Texas have the power, unrestrained by the Constitution for the United States of America or any law passed by Congress, to use the militia to protect their citizens and borders from the human invasion flowing north. In fact, the individual States, when “actually invaded, or in such imminent Danger as will not admit delay,” have the constitutional authority, independent of the federal government, to engage in war when necessary.”