Sith Shadow Council of Texas (SSCOT) -
San Antonio Star Wars Fan and Costume Group
https://sithshadowcounciloftexas.weebly.com/
501st Legion - Vader's Fist (excellent costume references for all Star Wars villains)
https://www.501st.com/
Texas chapter- https://www.stargarrison.com/
Sith Lord costume references- http://www.501stsithlords.com/sld-crl.html