Machinechads - I need a few small parts tapped but don't want to get it thread milled and pay my guy hundreds to buy the tool and labour.

How can I do this myself?
Metal: sterling silver (cast with 1.6mm dia holes)
Need to tap for M2 screws. 0.4mm pitch
M2 has a 1.567mm minor diameter, 2.0mm major diameter.
What exact taps do I need because I see a few different types out there.