The servo rudder you are looking for is here, all sizes and mounting types are available!
Reference 08293422
Brand: HUDY
ALU CLAMP STEERING SERVO HORN - EXTENDED 8mm - 25T - 293422
Reference 04SRT-TRX7
Brand: SRT
2 holes 24mm 25T SRT steering servo horn with offset - SRT-TRX7
Reference 08293406
Brand: HUDY
ALU CLAMP SERVO HORN - FUTABA, SAVÖX - 2-HOLE M3 - 25T - 293406
Reference 04SRT-TRX6S
Brand: SRT
1 hole 25T SRT steering servo horn with offset - SRT-TRX6S
Reference 08293409
Brand: HUDY
ALU CLAMP SERVO HORN - FUTABA, SAVÖX - 3-HOLE M3 - 25T - 293409
Reference 08293402
Brand: HUDY
ALU CLAMP SERVO HORN - HITEC - OFFSET 1-HOLE M3 - 24T - 293402
Reference 08293499
Brand: HUDY
ALU SERVO HORN - FUTABA, SAVÖX - 2-HOLE M3 - 25T - 293499
Reference 08293496
Brand: HUDY
ALU THROTTLE SERVO HORN - FUTABA, SAVÖX - OFFSET 2-HOLE M3 - 25T - V2
Reference 08293405
Brand: HUDY
ALU CLAMP SERVO HORN - HITEC - 2-HOLE M3 - 24T - 293405
Reference 08293509
Brand: HUDY
ALU THROTTLE SERVO HORN - FUTABA, SAVÖX - 2-HOLE M3 - 25T - V2 - 2935
Reference 08293494
Brand: HUDY
ALU THROTTLE SERVO HORN - KO PROPO, SANWA - OFFSET 2-HOLE M3 - 23T -
Reference 08293502
Brand: HUDY
ALU SERVO HORN - HITEC - 3-HOLE M3 - 24T - 293502