Howdy,
If you're referring to the Dell toner cartridges, NY313 and NY312, they do not yet have NSNs. However, you can order them both from GSA Advangage at the links below:
NY312 - DELL 5330DN BLACK 330-2044 10K YIELDand
NY313 DELL 5330DN - HIGH YIELDThe MSDS for these cartridges is available
here.
If it's not toner cartridges that you're looking for, please update this post with more information on the particular item that you're trying to find.