Source:  https://sourceforge.net/projects/advancedhmi/files/advancedhmi/3.5/AdvancedHMIV399xPatched3.zip
Downloaded on 2018-11-19.

DLLs can be found in AdvancedHMIV399xPatched3.zip:

./AdvancedHMIDrivers/Support/OPC/OpcRcw.Sec.dll
./AdvancedHMIDrivers/Support/OPC/OpcComRcw.dll
./AdvancedHMIDrivers/Support/OPC/OpcRcw.Hda.dll
./AdvancedHMIDrivers/Support/OPC/OpcRcw.Comn.dll
./AdvancedHMIDrivers/Support/OPC/OpcNetApi.Xml.dll
./AdvancedHMIDrivers/Support/OPC/OpcRcw.Batch.dll
./AdvancedHMIDrivers/Support/OPC/OpcRcw.Da.dll
./AdvancedHMIDrivers/Support/OPC/OpcRcw.Cmd.dll
./AdvancedHMIDrivers/Support/OPC/OpcNetApi.dll
./AdvancedHMIDrivers/Support/OPC/OpcNetApi.Com.dll
./AdvancedHMIDrivers/Support/OPC/OpcRcw.Ae.dll
./AdvancedHMIDrivers/Support/OPC/OpcRcw.Dx.dll
