If you export the default filter set in XML format (using SPCC > Filter Management) and open the resulting .xpsd file in a text editor you will find some of the filters have a "reference" field defined as a URL. These URLs typically identify a data source on the manufacturer's site; sometimes the URL is a manufacturer's home page, and you will need to dig deeper to find the product data sheets with the filter / QE curves.
I'm not aware of any wider repository. Since much of this data may be regarded as manufacturer's IP, there may be legal issues about publishing a combined data repository.