I'm not sure what other brand motor mount is a direct fit like you want but what about milling the stock V5 motor mount plate thinner to move the motor closer to the center? You could remove 1.0-1.5mm from the motor side and still have a structurally sound motor mount I would guess.
Tamiya 417v7 Sedan, ___ Tamiya 417v7 USGT, ___ CEFEX EVO w/ 417 suspension VTA
Exotex TA06 Pro CS Drifting, ___ Tamiya 417v5 (sold)
AE SC10 4x4
AE SC10 AE B4.11