3D-PSSM template database is not update any more (it's from 2004!) as stated on its website. It has been superseded by Phyre.
I would recommend to try HHPred, which is one of the best, if not the best template finding server.
To try other servers, the fastest way is to use a METASERVER (e.g. http://genesilico.pl/meta2/ from my previous lab), which will submit your sequence to several servers automatically.
If you indeed cannot find a template with those tools, try indeed Rosetta or I-TASSER.
Note that de novo modeling more often fails than works, so I would think twice before spending time on that (do you expect to answer you biological question with very uncertain de novo model?).