We have been told that it's difficult to impossible to rebuild the 5.0L V-8. Now we know several guys on this forum have done it so it is possible but not easy.
I found these guys selling rebuilt 5.0 V-8's on EBay for $12500! But the real interesting thing is they claim to use upgraded stage 3 parts. Whatever those are??

Rover Parts Depot is their name and they carry a bunch of hard to find internal hard parts. Like pistons, rods, valves, bearings and complete rebuilt engines.
The thing that stood out is in the description they mention 11mm head bolts and 11mm timing tensioners and chains. I do know Jaguar went from 6mm to 8mm stuff as they upgraded the 5.0L engine over time.

5.0L Parts and Engines

Does anyone know more about these upgrades? Do 11mm tensioners exist?
.
.
.

 

Here is another source:

https://text-a-part-auto-jaguar.business.site/

I spoke with the owner, Keith, and he seems very knowledgeable and confident with his work.

 

I looked into Rover Parts but didn't have time to weigh my options when my engine went down. I have a salvaged 2011 engine in mine now, with around 72k chassis miles and 48k engine miles.
Since l have the ZF 6 speed, uprated engine parts I could not take advantage of right away, and I decided was outweighed by cost/benefit. This looks to be a really nice set of options now that NBCat has chimed in. The key about these shops is reputation, and I see positive feedback on an actual recent install on the shop NBCat recommended.

It looks like the user in the Range Rover forum paid about $14k for the engine with 0 miles/updated parts, and that includes the return core being sent back to them.
https://www.rangerovers.net/threads/...graphy.349846/

I got my used engine before prices started to climb. It was $9300 shipped and they included the supercharger (not sure if that was a mistake or not, but I got two now) lol.