Serge-
Still say it sounds very much like a connecting rod bearing. Here is a test you can perform to narrow the issue down.
With the engine running - one at a time remove the spark plug wires. If it is a connecting rod - you will hear a noticeable drop in the volume of the noise when the plug wire on the offending cylinder is removed. This is caused by the lack of pressure in the cylinder when no combustion occurs. If it is the roller cage issue - removing the wires should make no difference in the volume.
Good Luck-
Glenn