HCI and BW - Ability to call HCI task from BW (7.3) Process Chains

HCI Gurus,

Need an advise....

One of our customer  is using BW (7.3 not 7.4). BW is single source of data source for IBP. For initial go-live, manual data loads done and plan is to start HCI for automatic loads.

Need is BW process chains to call HCI tasks (Push data from BW to IBP) and in order to achieve this, we are planning to use Web Services from BW.

Question :

I was given an understanding that Web services option is not available in BW 7.3...Could you please share your experiences on this topic? Is there any other way to achieve this functionality of pushing data from BW to IBP.

Thanks,

Krishna