Sao Francisco baptismal records are online https://familysearch.org/pal:/MM9.3.1/TH-266-11542-149609-64?cc=1719212&wc=MMLV-R91:n1559026046#uri=https%3A%2F%2Fapi.familysearch.org%2Frecords%2Fwaypoint%2FMMLJ-1C2%3A1619731926%3Fcc%3D1719212
I was able to look for June 1, 1960 up to the page 141 and then the service become unavailable. You would have to look for pages 142 to 149 (December 1960). I have found some Maria de Lourdes but her surname as well as her parents' names did not match. Maybe she was not baptised. Or baptised from 1961 on, which is not online.
They have marriage records, too, so you can look for your grandparents, assuming they married in Sao Francisco. By the way, a word of caution: there are places named Sao Francisco de Paula, Sao Francisco de Sales, Sao Francisco do Gloria, all in Minas Gerais state, but they are not available on line, so far.
The Civil Register Office in Sao Francisco: Cartório do Registro Civil das Pessoas Naturais Pç. do Centenário, 431 - Sala 102 Centro 39300-000 São Francisco MG e-mail:firstname.lastname@example.org (don't know if it is still valid, or if they answer queries by email.