Tiny RF locator

I’m looking for the smallest RF locator receiver for my god sons high school engineering project. He’s got a great idea but the receiver needs to fit in a very small location. The transmitter has no size restrictions which is opposite from how these things usually work. Any help is greatly appreciated.

I am not locating any finished RF locator modules that will be of any use to you. Have you looked at of the locators used for finding your missing keys etc. but we do not carry them. they may be found on the internet. These appear to have smallish receivers which may work for you. The technical reference number is T4192618
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