The Commissioner of Revenue Services is authorized to pay to a revenue agency of another state an amount not to exceed fifty per cent of the tax actually collected as the result of an assessment made under section 12-416 against any purchaser of tangible personal property or services described in subdivision (2) of subsection (a) of section 12-407 if said commissioner, in the commissioner’s sole discretion, determines that information provided by such agency was instrumental in the making of such assessment.