I'm not trying to argue with you just pointing out why this truck is not flying off the shelf. But since you asked. The drive flanges are one, which there is someone on pirate right now trying to find some. To replace the ones he had. Then Stub Axles is another. I remember several threads where Jake was trying to find some to replace one that got messed up on this truck.
If the kit was bought from Keith. Then all you would have to worry about is axles and he's told me and others that if axles are needed then to just give him a call. Toy diffs and parts are readily available. And the custom stuff from Keith are very substantial
Even if Keith has made that offer. It's not like he's got those laying on a shelf he's going to have to order them and then machine them. So the turn around on that will be less than speedy. If Keith happens to change his mind or get hit by a bus. You'll need need to find someone else to make custom axles. Can it be done? Certainly, is this something the average rover owner will want to mess with? Probably not.
Honestly, I've considered buying this truck and if it was closer I would be looking at it. I also considered buying Jake's DI when it was for sale. The reason I didn't is because I want something that's trail fixable and where parts are readily available. I still think this truck is a good deal to the right buyer. The problem is finding one.