The Marxists Internet Archive has several texts by atheist priest Jean Meslier (1678-1733) collected in a Jean Meslier Archive:
The latest addition is the Conclusion (1728) to Memoire des Pensées et Sentiments in Oeuvres de Jean Meslier.
Note also a new print publication of the Marxists Internet Archive:
The Great Anger, Ultra-Revolutionary Writing in France from the Atheist Priest to the Bonnot Gang: A collection of texts and essays edited and translated by Mitchell Abidor. Published by Marxists Internet Archive Publications, 2009.
This is available from Erythrós Press and Media Store.