Parts are available at Jaycar part numbers below

2 x BC556 Transistors - ZT2162
1 x BC546 Transistors - ZT2150
3 x 1N4004/7 or IN4148 Diodes - ZR1004/ZR1007 or ZR1100
1 x 4.3v 1N4731 Zener Diode - ZR1401
3 x 22k Ohm resistor - RR0604
1 x 27k Ohm resistor - RR0606
1 x 1K Ohm resistor - RR0572
1 x 10k Ohm resistor - RR0596
1 x Plastic box 54 x 83 x 30mm  - HB6015
1 x DB9 Female connector - PS0804
1 x Small Vero Board - HP9540

2 x Feinmetal F62011S120N075 Spring loaded connecters. (Not available from Jaycar)