Ill check out the bands you mentioned, Ive heard Stiff Little Fingers(Alternative Ulster was on of the first songs I learned on electric) before and I never thought they were too similar to Butch but Ill give it a go.
If your interested in Butch, check this place out: http://www.gnr.com.ar/cgi-bin/yabb/YaBB.cgi?board=walkatorium
www.gnr.com.ar
http://www.izzystradlin.tk/
http://www.izzystradlin.tk/