Where to get filter for spectroscopy?

[bolo]

Hi I need to play with simpe gas spectroscopy. At start I think about oxygen who have asbsorption line at 760-770nm (so I can use simpe silicon). Any idea where I can find this filter in not big price?

[macona]

Nothing in the astronomical wavelengths that you can use, they are some of the cheaper filters since they are mass produced. Edmunds or Thorlabs might have on. Or you could use a grating and a couple of slits and mirrors like a traditional spectrometer.