Limit Switches

Two of the limit switches are inoperative on my Seig X3.
They are flimsy plastic units, marked V3S, having yellow, red and blue wires. The blue is redundant in the series wiring for Mach 3.
Could anyone suggest better units, suitable for replacement. With the source of purchase, if possible please. The available choices are, I am afraid, a bit overwhelming to a non electrician.

V3 is a standard size of microswitch.
If you do a google search for V3 microswitch, you'll get lots of options. The main thing is you get one with the correct style actuator. There are also options for connectros/leads, different levels of sealing, and off course how much you want to spend.