Self tappers are designated in wire guage size. Not Dia x pitch.
Specifying a pitch of 1.25 on a 6mm screw is more course than a std metric course 1mm pitch.

Bottom line is you wont find what you have specified unless you intend to get them made.

Searle's will no doubt have what you want though if you can figure out what it is you need. They have a good range of many tamper proof fasteners.

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MY00 WRX. 89 Prelude. 99 CRV