Yeah but remember the 80 series Land Cruisers are ~$55k vehicles to Toyota not $3k vehicles. The secondary market for any manufacturer is completely irrelevant when it comes to OEM parts prices. Which is why there is an aftermarket for people who consider their 80s $3000 vehicles.
Also...
This is the "problem" with the 80 series. They're so robust that by the time major components like the engine and transmission need replacement the parts won't be available. If money were no object I'd put a new short block and A343f on the shelf for the far off distant future. But it doesn't...