Well, small number(about 5-6) of Parus constellation sats still radiate navigational signal. But Russian Navy can use it for sending orders, reports, short messages, alarms, etc. Same as GRU using their Strela/Gonets constellation.
I might add:
"Parus" satellites provide space communication and navigation information for submarines and surface ships of VMF RF in all areas of the World ocean. They form the battle space navcom system called «Cyclone-B», providing a navigation and distant bilateral radio contact with the active rebroadcasting through other satelites, submarines and surface vessels in the World ocean. The system was accepted on in service in 1976 and modernized repeatedly."