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KX125 Keihin Slide Throttle Valve Broke...best option?

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I have a 1992 KX125. I've had it for 14 years. I take good care of it and can't seem to part with it.

I was working on it today. Fired up first kick and ran beautifully. Started warming it up, twisted and released the throttle a few times and suddenly it wouldn't idle. Only had trouble at idle, so I wasn't worried about it being a mechanical issue. It was acting starved for fuel at idle.

Long story short, I pulled the carb off and found that the throttle valve had cracked and the lip that meets the idle adjustment screw broke off. Time and fatigue. That's all I can assume.

So I went on bike bandit and searched for the OEM part. To my disgust I found that it is an $88 part. That's when I decided to scan eBay. I can find a whole "new" carb cheaper than that. Well I can find lot of KX keihin carbs, but not a 92 or 93 KX125 carb.

I found several possible alternatives. I found a carb from a 92 KX250. Unfortunately that's a bigger carburetor and the stock throttle valve cut is a 7 as opposed to my 5. Just buying it for the parts wouldn't work. So run the bigger carb? What would that be helpful or harmful? Would I have a hard time getting it jetted right?

I also found a couple of KX125 carbs from the mid nineties. I'm not certain what size they were running on a 97 for example. But it appears to be an "air striker carb." The difference isn't real clear to me except I can see some vent tubes on the top of the carb. Would one of these work for my application? Could it be considered an upgrade of sorts? Will I have room for the vent tubes on top?

Or should I just break down and spend the $100 bucks out the door on the new OEM throttle valve?

Any input is much appreciated. Thanks.

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