That's not quite correct crowbar. 86 is relay coil positive. 85 is coil negative to ground. 30 takes your fresh fused feed from battery and 87 is that relay switched feed out to lamps.

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Generic 4 or 5 pin cube shaped 12 volt 30/40 amp relay will work fine (ignore 87a contact on 5 pin).

Richard

2018 Roadster 3.7
1966 Land Rover S2a 88
2024 Royal Enfield Guerrilla 450
1945 Guzzi Airone