I doubt you will find many like that unless they stick out from your side really far. The majority of the americans, even gun carrying ones, are overweight so manufacturers take that into consideration that they may not be able to shove their fat thumbs in their to hit the release if their life depends on it.

Not trying to be controversial, just saying exactly how I would think of it from a manufacturing perspective. I wouldn't design anything that low profile that relies on a release on the inside edge.

That being said, I can understand exactly why you would want one and if you have the physique for it then go you. I like having a "body side" thumb break on my thigh holster because it makes it that much harder for someone to get your gun from you.

BUT that is also why I am a huge pusher of only concealed carry when possible. I was so paranoid when carrying for work because everyone could see I was carrying and exactly where and how to get it.