Yes—IR-cut and IR/UV-cut filters are commonly available, especially from optical and astrophotography suppliers. For prototype materials, specialty optics vendors such as Edmund Optics are a good place to check. In photography, these filters are often sold for astrophotography because many refractive telescope systems are corrected mainly for visible light.

The main limitation is material: based on the answers, plastic IR-cut sheets are not commonly known or widely available. Unmounted glass filters are more likely to be available than plastic ones, and some astronomy filter makers may offer them. Mounted versions are definitely common.

If you need a custom shape, an unmounted glass filter may be your best bet, but cutting it cleanly can be difficult, so you may need to experiment or adapt your design around a standard filter size.