A very small list this one:
Australian Opening Batsman to Score a Test Century in India
Usman Khawaja - 4th Test, 2023
Score: 104 (still batting)
Innings: 1st
Ground: Ahmedebad
Shane Watson - 1st Test, 2010
Score: 126
Innings: 1st
Ground: Mohali
Simon Katich - 4th Test, 2008
Score: 102
Innings: 2nd
Ground: Nagpur
Matthew Hayden - 3rd Test, 2001
Score: 203
Innings: 1st
Ground: Chennai
Matthew Hayden - 1st Test, 2001
Score: 119
Innings: 2nd
Ground: Wankhede
Mark Taylor - 3rd Test, 1998
Score: 102 not out
Innings: 4th
Ground: Bengalore
Geoff Marsh - 3rd Test, 1986
Score: 101
Innings: 1st
Ground: Wankhede
David Boon - 1st Test, 1986
Score: 122
Innings: 1st
Ground: Chennai
Graham Yallop - 5th Test, 1979
Score: 167
Innings: 1st
Ground: Eden Gardens
Keith Stackpole - 1st Test, 1969
Score: 103
Innings: 2nd
Ground: Brabourne
Les Favell - 4th Test, 1960
Score: 101
Innings: 1st
Ground: Chennai
Jim Burke - 2nd Test, 1959
Score: 161
Innings: 2nd
Ground: Brabourne