I need a trusted advice for the following scenario:

You have 3 computers running openERP separated geographically, 2 dedicated to serve as POS & 1 serve as server.

I don't want to connect POS's to server using internet connection, instead I want to export POS's oreders, sessions, journal entries and any sales related records and import them into the server, also I need to generate a new sequence(e.g POS0001, MISC/2013/0001) for all exported records in the server. is that possible? if yes, what tools should I use/build?

I need to do this exportation once per month.

Advices, Hints are highly appreciated..%