Are any of these servers what you are looking for?

Servers with "Server" and "Test" in the name:
S@V3D Test Server
CS:S Gameserver Test
cwg| Test Server | Maps Mods Plugins - cwgrocks.net
Match-Gaming TestServer
Static-Gaming.com | Testserver
Kollaps Test Server
Test Server CS:S by GameGroup.com.ua
MServers.org.ua CS:S v78 Test Server
Science System Testserver
nitrado.net CS:Source - Testserver