Allparts make pickguards, control plates and switches for Jaguars, so if there was a body/neck only kit, it would be possible for people to source the other parts required themselves. Allparts Jaguar bits
It might even be possible to speak to the Australian Allparts distributor (RealTone music), to see if they were prepared to put a standard Jaguar parts kit together at a discounted rate, where you only need to chose the colour of pickguard and hardware you wanted (or even limit it to chrome to make it easier). It's obviously going to be more expensive than a bag or parts from China (though they are still probably made there), but if you are committed to making a Jaguar, then it would be a worthwhile outlay.