ok, the brother of the owner and i created a new one for the passenger side, the easiest thing i could suggest you could do is to create a JIG from your existing one including templates for the end plates, hole locations etc
this would allow you to get these done extremely cheaply. and be easier than us designing them for you since we are using engine mounts from a jap spec corrolla (dont ask - they were already on it)
take the JIG and the existing ones to an engineer, this would allow them to ceate them without having to work it all out, hence they just cut the steel and welding it for you.. would be stronger and the they wouldn't have to spend much time creating them. which will make it cheaper. take most of the labour out of the equation.
the gearbox mount was simply a standard gearbox mount with the centre modified and a reinforcement plate welded to it to align with the mounting holes on the ca18 box ... not too much work involved, although the gearbox and everything is back in the car so i cant get photos for you.
we have welded the new rear quater skirts and tailgate back on to remove the rust, the modified lower control arms have been lengthened and reinforced .. they are bolted back in , just waiting on the new custom sway bars to arrive. adjustable strut tops are in place.. just have to find a shock setup to allow a high level of lowering while maintaining a wide range of motion before bottoming out.
can you confirm if the front suspension of an MR2 is usable on these?
oh and use a higher grade of steel on the engine mounts.. what rubbers are you using? try and find something that has a harder compound.. as ours are a bit soft to cope with the ca18's power/torque movements.