The Infineon BC807-25E6433 is a PNP general-purpose transistor in the standard SOT-23-3 package. The 330 mW power dissipation is typical for this footprint; keep the junction temperature at or below 150°C and it will behave.
The DC current gain (hFE) is specified at a minimum of 160 when collector current is 100 mA and Vce is 1 V. That is a usefully high gain for a PNP of this current class — you can drive the base with a few milliamps from a logic output or a small-signal NPN and still saturate the transistor hard. The Vce saturation is 700 mV maximum at 50 mA base current and 500 mA collector current, which is typical for a 500 mA-rated PNP in SOT-23. If you are switching a 300 mA load, budget about 0.7 V drop across the transistor; that is fine for a 12 V rail but worth watching on a 3.3 V supply where every millivolt counts.
Package and field-replacement reality
The BC807-25E6433 comes in a PG-SOT23-3-11 package, which is the standard SOT-23-3 footprint. That is the same pinout as the vast majority of SOT-23 PNP transistors, so if you keep a few of these in your field kit, they will swap into almost any board that uses a general-purpose PNP in that footprint. No lab bench needed — just tweezers and a soldering iron.
For a repair or retrofit, you are not chasing obsolete stock.