Luis,
I've been doing a lot of google searching too. I found these links useful:
SkyCam project (recommends L163VDC4P )
Sonota Recommendations (recommends Fujinon YV2.7x2.9LRD-SA2)
These are more expensive options.
I have found it quite difficult to find reasonably priced / good quality CS 1/2 wide angle lenses here in Australia. I suppose Argentina has the same problem.
The DX option is only a few dollars, so could be worth a try. Let us know how you go.
James