Edit: Before you read my dissertation below, go to this www and select switch type KS-2. I think it will be what you are looking for:
https://thmarinesupplies.com/products/saf-t-stop-kill-switches-for-boats
Since the KS-1 is listed for outboards specifically, and KS-2 is listed specifically for I/Os obviously there is a difference and what you are looking for. A quick call to a knowledgeable clerk could clear up any confusion........if you are board with nothing to do, then read my dissertation....grin.
The dissertation:
My service manual is for 2 stroke outboards of 75-125 HP between '94 and '05. It only lists the Commander 2000 which is the side mount TO the bulkhead, not IN the bulkhead like the 3000 with it's big black button to push for throttle only starting assist. Since I have replaced a 3000 with a 2000 on a different boat and everything worked accordingly, they must be pinned out and wired the same, and the 3000 in my current Crestliner is pinned out as is shown in the manual for the 2000.,,,,,
I'm making this distinction due to your saying the "Purple wire". Since you are running an I/O with a marine converted auto engine, they may have "rigged" your ignition off the Purple, switched power and as such your ignition would be shut down with the loss of 12v as would be the case with the ignition switch of the 3000 in the OFF position, or in the case of the switch you mentioned, it opened. Nothing magic about the switch. You can go online to ebay and buy a 10 amp SPST, water resistant switch for a song....the water resistant switch having a rubber boot over the toggle mechanism.....you didn't mention a lanyard type special switch.......thinking about it, that is what I have with my 3000....the switch is separate from the Commander 3000 unit. On my outboard engine you need to have the switch "closed" to kill triggers.....short them to ground. On your engine you need to "remove 12v" to kill the ignition which means, as you said, to OPEN on when activated. OKayeeeeee. Different ball game. I don't know who makes the switch but apparently there needs to be an opposite polarity lanyard safety switch for converted auto engine style ignition system.
I can't sleep, making the transition from -4F to +50F tonight, maybe I'll dig around and see what I can find.
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On the control internal wiring: The Red wire is hot 12v from the battery, via the engine wiring harness connector.
Purple or Red with Purple stripe is 12v power that has been applied to whatever needs "switched power" by the ignition switch being in the ON-START position.
Black/Yellow stripe is the Ignition Kill wire from the control and is grounded when the switch in in the OFF position, grounding the ignition signal in the CDI modules, or the Emergency Stop Switch has been energized....lanyard pulled out of the socket.....per the 2000 wiring diagram.
Apparently they left the Black/yellow stripe wire disconnected on the boat wiring and pulled out the purple wire from pin 2 of the wiring harness and interrupted it.
