Hey Dunndog/Grip
Its for a LC Prado so has the two inch hitch so maybe it has enough carrying capacity on the towbar...found this on the specs 'permissible ball load of 250kg' however totally get the concern about somebody trying to mate it to a getz! A friend of mine has the actual NSR 6 on his LC and it hasnt fallen off yet! We use it for AM bikes tho not DH so loads will be around 120 - 150kgs (assuming 30kgs for the rack - NSR's weight).
The problem is, if we're only making a one-off for a customer (because as explained above I'm not interested in this being one of our "products") then someone has to pay for the design/prototyping cost and trust me... that would end up costing more than buying an existing product (where they've already done all of that).
This isn't an issue if you're building the thing yourself as a backyard, one-off hobby project where time isn't expensive, but no business could afford to do it without charging and at $90 per hour (our standard rate) you can see how quickly that would add up.
The bottom line with getting
anything custom made is that you either have to provide full tech drawings and engineering specs, OR an exact sample of what you're after so it can be copied, OR you have to pay for design work etc.