2 layers50 × 50 mm

The 53040C is a current Sense Transformer made by Murata in a SMD-8P,8.3x7.2mm package with 5 pins. 50kHz~500kHz 7mΩ Vertical welding SMD-8P,8.3x7.2mm Current Sense Transformers ROHS.
JLCPCB lists it (part C5530597). 1 open-source board in 1 repository on GitHub use it.
The library has no symbol for this part yet.
The library has no footprint for this part yet.

SMD-8P,8.3x7.2mm, with 5 pins.
Murata publishes it: the Datasheet link on this page opens it.
JLCPCB lists it as part C5530597, with 0 in stock; the sellers' links on this page open their listings.
1 board in 1 repository on GitHub; the most starred are listed on this page, with their KiCad files.