Most of the aromatic compounds e.g. organic dyes give good Raman signal. RBITC, MGITC, Rhodamine 6G, crystal violet, 4-MBA are some the examples.

Look for things which are symmetrical and do not fluoresce easily.  Cyclohexane is the default Raman standard and is fairly non-toxic and easy to work with.

In accordance my personal experience about  study stimulated Raman scattering I would recommend some organic solvent (instead  solutions of dyes as recommended scientists above) because  Raman signal is  elementary proportional not only scattering cross-section but also  to number scattering molecules. More  exactly I name the  aromatic liquids  like benzole and its numeres derivatives (but be carefull with operation). Naturally one  must take  into account that Raman scattering cross- section can be increased strongly as exitation frequency is  getting near to  own absorption band -resonance factor).

Proteins (as as well as peptides), nucleic acids (as well as oligonucleotides) give generally rise to intense (classical and in-resonance) Raman bands in solution. In the case of the peptides the most intense Raman peaks naturally correspond to aromatic amino acids and bring useful information on their environment in solution. Some useful information can also be obtained from the Raman data obtained from phospholipids through the analysis of the high wavenumber spectral region (above 3000 cm-1). Some excellent review papers are available on these subjects if you need.

Thank You Sir.