Since joining NATO, the Czech Military is currently updating all of it's arms to comply with NATO standards including the use of 5.56mm ammunition.
The Czech military has placed orders for several new weapons including M4s from Belgium and the US, Steyr AUGs from Austria, and several others including some indigenously developed small arms. The Model 58 that you show is still in use, often by border patrol/border guards, police, and non-military personnel requiring somewhat heavier weaponry than pistols.