Welcome to Ireland Reaching Out!
I presume your Smith ancestors were Church of Ireland. The baptismal records for Elphin C of I church start in 1896. This link takes you to the status of records by parish and it appears that 19th century Elphin records were destroyed in 1922 but some records were located later https://www.ireland.anglican.org/cmsfiles/pdf/AboutUs/library/registers/...
The records available are maintained at the Representative Church Library in Dublin.
You may also want to contact the Elphin Branch Library and see if they have any information on the Smiths. As ana side, most of Ireland and certainly public offices will be closed thru the weekend because of Storm Emma.
Elphin Branch Library
Main Street, Elphin, Co. Roscommon, F45 VW27
Branch Librarian: Penny Farrell
Tel. 071 9635775
Thursday: 2.30pm to 6.30pm
Friday: 10.30am to 1.00pm and 1.30pm to 4.00pm
Saturday: 10.30am to 1.30pm