i just finished changing out a range hood in a nieghbor's house. they are not that expensive and all a standard size.
i would imagine one could put a moderately priced stainless range hood with improved lights and better fan for around $150. the fan could be left 120 volt or converted to 12 volt
if you have the hood mounted control panel for tank and battery level it could be added to a regular hood with minor modification.
lighting would be easy as well, just connect the standard 120 volt sockets to the existing 12volt wire, then purchase 12v
standard lamps. (wal mart has them)