Is it possible to aggregate PUMAs to the metro area?

This 5-year ACS uses the 2000 vintage PUMAs. You can get the maps from https://www.census.gov/geo/maps-data/…. You’d have to match up your target geography to these maps. With some luck, MCDC geography converter will have your metro area (http://mcdc.missouri.edu/websas/geoco…)