I do not know where it is but here is proof that there is a town like them in Galicia (the part of Poland under Austro-Hungarian occupation)
Born in Estrich, Austria (province of Galicia on 16 May 1887 to William Szewczyk and Margaret Schnell. Christina Szewczyk married Jacob Kielbasa and had 4 children. She passed away on 1963-04-19 in Caldwell, NJ.
Born in Estrich, Austria on 6 Aug 1864. Frank Joseph Ditchman married Anna Lee White and had 1 child. He passed away on 11 Feb 1951 in Houston, Harris, Texas, USA.
Perhaps then Estrich simply means someone from AUSTRIA and AUSTRIAN.