Hi,
The HWIC-1DSU-T1 is a new module, see here:
http://www.cisco.com/en/US/prod/collateral/modules/ps5949/qa_c67-490366.html
It's functionally the same as a WIC-1DSU-T1-V2 (assuming you really meant the V2 version as the original is nearly obsolete) and as it does the same job as the WIC I'd expect the WIC to become end-of-sale shortly as it's clearly a replacement product.
HTH
Andrew.