There was an enquiry in the Scotland board regarding the family Coste and these are the few Scottish records for your information.

Births:
1 1867 COSTE ELIZABETH F CLYDE LANARK 644/05 1061
2 1867 COSTE ELIZABETH F GLASGOW CENTRAL DISTRICT LANARK 644/01 2137
3 1860 COSTE FRANCIS M BLYTHSWOOD LANARK 644/06 0179
4 1860 COSTE GEORGE M BLYTHSWOOD LANARK 644/06 0180
5 1863 COSTE MARGARET F BLYTHSWOOD LANARK 644/06 0038
Marriages/Male
1 1857 COSTE THOMAS EDWARD SORBIE AGNES PAISLEY MIDDLE CHURCH RENFREW 573/03 0046
Deaths
1 1895 COSTE MARIA F 75 PARTICK LANARK 646/03 0248
2 1925 COSTE MARY ELIZA F 79 NEW OR EAST KILPATRICK DUNBARTON 500/01 0046
3 1908 COSTE SARAH F 63 MILTON LANARK 644/09 0194