This surname is a little far back in my ancestry, but I have some information about my g-g grandfather's Mother who was Haberstock. This family's records are in Marktoberdorf Parish and they lived in Fechsen, Ostallgau, Bavaria. My g-g-g Grandmother was Anna Catherina Haberstock b. Apr. 7, 1786 in Fechsen and her parents were: Johann Peter Haberstock and Maria Anna Holzmann.
I have some of the early Marktoberdorf Roman Catholic Parish records on permanent loan from the LDS so I would be glad to do lookups and try to make connections.
Good luck!
Jim