The servo rudder you are looking for is here, all sizes and mounting types are available!
Reference 08293406
Brand: HUDY
ALU CLAMP SERVO HORN - FUTABA, SAVÖX - 2-HOLE M3 - 25T - 293406
Reference 08293493
Brand: HUDY
ALU SERVO HORN - FUTABA, SAVÖX - OFFSET 1-HOLE M3 - 25T - V2 - 293493
Reference 04SRT-TRX6
Brand: SRT
2 holes 25T SRT steering servo horn with offset - SRT-TRX6
Reference 04SRT-TRX5
Brand: SRT
2 holes 25T SRT steering servo horn - SRT-TRX5
Reference 08293497
Brand: HUDY
ALU SERVO HORN - KO PROPO, SANWA - 2-HOLE M3 - 23T - 293497
Reference 08293503
Brand: HUDY
ALU SERVO HORN - FUTABA, SAVÖX - 3-HOLE M3 - 25T - V2 - 293503
Reference 04SRT-TRX7
Brand: SRT
2 holes 24mm 25T SRT steering servo horn with offset - SRT-TRX7
Reference 08293495
Brand: HUDY
ALU THROTTLE SERVO HORN - HITEC - OFFSET 2-HOLE M3 - 24T - 293495
Reference 08293502
Brand: HUDY
ALU SERVO HORN - HITEC - 3-HOLE M3 - 24T - 293502
Reference 08293506
Brand: HUDY
ALU THROTTLE SERVO HORN - FUTABA, SAVÖX - 2-HOLE - 25T - V2 - 293506
Reference 02UR1804
Brand: ULTIMATE
ALUMINIUM DOUBLE ARM SERVO HORN (23T - SANWA/KO/JR/AIRTRONICS) (1pc.)
Reference 02UR1805
Brand: ULTIMATE
ALUMINIUM DOUBLE ARM SERVO HORN (24T - HITEC) (1pc.) - UR1805