Is there a Windows Performance Counter which contains the "Log Send Rate" for Availability Groups? I wish to be able to get the "Log Send Rate kb/s", as per the SSMS AG dashboard (which is also available via log_send_rate column on the DMV sys.dm_hadr_database_replica_states)

I'd like to get it as a Windows Performance Counter... looking at the available counters for the Database Replica category, the nearest is "Log Bytes Received/sec", which doesn't appear to report the same value. 

Does anyone know if there is a performance counter or will I need to rely on the DMV?
The DMV column log_send_rate will tell you Rate at which log records are being sent to the secondary databases, in kilobytes (KB)/second.
Depending on what SP + CU you are running, you may want to look into - KB 3012182 FIX: Log_Send_Rate column cannot reflect the rate accurately in SQL Server 2012 or in SQL Server 2014
Below PERFMON counter will tell you how many bytes were sent

SQL Server:Availability Replica --&gt; Bytes Sent to Replica/sec
Number of bytes sent to the remote availability replica per second. On the primary replica this is the number of bytes sent to the secondary replica. On the secondary replica this is the number of bytes sent to the primary replica.