Those modules are available online if you Google for “poe module” and are not too expensive, but I do not know if they are in stock. They come in different voltages and I think the GL-B1300 is 12V. You also need a PoE injector or a PoE switch for power supply.
The AliExpress device is labelled DP9700-5V POE module, but the description states 12V ??
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