The 62 series of power relays from Finder. With various mounting types available, which include PCB, plug in and flange, you are sure to find a suitable version. A Reinforced insulation between coil and Contacts according to EN 60335-1, with 6 mm clearance & 8 mm creepage distance makes them perfect for your application.
DPNO and 3PNO have a 3 mm contact gap Contact Material: AgCdO Isolation Coil To Contact 6 kV (1.2/50 μs)
Note
Magnetic blow power relay also available (8949405 and 8949414)