The meanwell rt-50b is also a simple option for a bench supply. For 15 euros, hard to beat. You just need to put it in a small enclosure to be safe on the mains side. If you don’t know how to wire mains, don’t do it, the voltages in there could kill you. That’s why you need an enclosure 
In europe, buy here : https://www.tme.eu/fr/details/rt-50b/alimentations-encastrables/mean-well/