Sandy,
A search on http://aidaonline.niedersachsen.de/ which contains an emigration list among
other references seems to point to a concentration of Bostel families in Isernhagen and
Burgwedel both of which are located just to the Northeast of Hannover city proper.
Perhaps, a review of church books in the Isernhagen and Burgwedel area could provide
a positive result?
Bob Behnen