Here are a couple of pages of third surdo parts, transcribed (one could say stolen) from a book purchased by a friend in Brazil, O Batuque Carioca, by Guilherme Goncalves and Odilon Costa. These are similar to some of the bass drum parts in my samba builder download (v. 2 coming soon!), but authentic- my parts are good coordination practice, but these are the real deal. Play all notes open, letting the beater come away from the head. Where possible (and where it makes musical sense) you could try adding a short/dead stroke on beat one.
Worldsamba.org says about O Batuque Carioca: "Written in English and Portuguese, this book details the history, terminology, instrumentation, and written notation for samba played in Rio de Janeiro. With detailed tablature [actually conventional notation- tb] for each instrument, groups of instruments, and the rhythm sections from the great schools of today, this is the one and only book you will need to get started in creating your very own "batucada" Rio-Style!"
Good luck finding it in North America- there is an email address for the publisher included in the pdf, though it is from 2000, and may well no longer be in service. The bold, determined, and Portuguese-speaking can try calling the store in Rio where it was purchased, Casa Oliviera, at 021 2325 8109.
Download the pdf.