Not sure what you're asking for, could you elaborate a bit?
Jamaica Plains (often times shows up as JP on hand written records) is a part (south, south-east) of Boston. Usually shows up as part of W Roxbury in the 1860-1880 timeframe.
Mass vitals are a little tough after 1920, privacy reasons, unless you're in Boston. However, NEHGS and Ancestry.com has a lot of the indexes (no certs images) that get you close.
The 1940 census may just have Boston not Jamaica Plains.
Igor (had a lot of relatives on Green, Tower, Union, and Rowen Ct. in Jamaica Plains)