Ultra mini acceleration switch

I am looking for a mini acceleration switch for my application. It will be high volume, 1-5 million in quantity or better when in final production. It have to be really TINY and light weight. Packaging is not as critical since we do epoxy coated the entire unit. The current unit we use used a reed switch. Due to difficult situation, we cannot use a magnet, and we truly believe the only other way to improve upon and maintain the functionality of the application is to use acceleration switch that can detect reliably the acceleration (150 fps). The reed switch we current use is SRC UM2325.

Any help or suggestion is sincerely appreciated

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