Full list of all 11 Half-Life: A Place in the West achievements. It takes around 0-1 hour to unlock all of the achievements in the base game on Windows.
The base game contains 5 achievements, and there are 2 DLC packs containing 6 achievements.
Finish Following Portents
Finish The Charnel House
"Beat" Half-Life in record time.
Disembark from the church
Survive the gonarch
Heroically listen to the entirety of the Following Portents commentary
Reunite old foes
Escape the antlion horde... on horseback!
Discover Operation Exodus
Find the kidnapped children
Check-in at the Franklin Motel