One of the best sources for pyroelectric sensors is a Florida company called Eltec Instruments. They sell standard off the shelf and custom designed sensors and sensor arrays.
These sensors can be equipped with a pinhole and scanned across the laser beam to create a 3D intensity profile using an O-scope or using a data acquistion system.
http://www.eltecinstruments.com/
The best way to get information is to call their top technical guy, David Cima.