You could use Verodes, which is a free stripboard layout tool. It allows population of simple components and allows you to see the underside and cut tracks as you need.
The circuit is quite simple.
First thing I'd do is lay out the parts roughly as they are in the diagram. Use a combination of the copper tracks and links on the top side to form your circuit. As a clue though whenever you see a horizontal line use a copper track. When you have a vertical line use a wire or a component to drop down to the required rail. So try and use your buzzer, switched and resistors in the vertical direction. I doubt you need to cut any tracks with this circuit.
Edit: it's an SCR. Never dealt with them before.