I am planning to prepare for the SCDJWS and I am in the process of collecting all the materials . Just to make sure I want to know whether there are any mock exams available for this exam (free of cost ) .
Unfortunately I too could not find any mock tests for SCDJWS 5.0, absolutely free. But you can obtain a mock test from Mikalais' link which you posted. You can get additional information about that test from Mikalai. Also Sun has couple of mock tests but they charge $65.