Well, that sucks.
There are lots of things you can do, you decide what to do, but this is my opinion.
I don’t think the lift pump is the problem, in fact don’t order a new lift pump until you measure fuel pressure (you can find instructions on how to do that on many forums and on the free version of the factory service manual). The lift pump is kind of expensive and shouldn’t be replaced just to see if it makes any difference. You have to be sure is bad.
Smoke could mean a lot of things: unburned fuel due to excessive quantity or poor quality, wrong timing, poor spray pattern, coolant or oil being burned, bad turbo, poorly adjusted ALDA, etc. Just lots of reasons for smoke to show up.
Neither do I think your problem is the turbo. Usually a failing/bad turbo causes other problems like power loss, excessive oil consumption, lots of grey thick smoke and drilling noises. Lumpy idle is not one of the symptoms as far as I know (unless the turbo failed spectacularly and sent pieces to the engine and those pieces destroyed the cylinder walls and piston rings, but your engine would be burning lots of oil and making agonic noises).
I don’t know if you have done a diesel purge, but is one of the first thing you should do (specially considering that is cheap, easy and quick) and very recommended when you have performance and smoke issues on a diesel. Over time dirt builds up inside lines, IP, injectors and the diesel purge cleans that restoring performance. If your injectors or pump are worn diesel purge won’t improve things, though.
Next, you have to adjust the valves and inspect the condition of the timing chain. Tight valves produce uneven compression, which in a diesel is a big problem. A loose chain can change IP timing. Adjusting the valves is “easy” (once you acquire practice) and the tools needed are cheap. IP timing can and should be adjusted every certain millage to compensate for wear.
After the valve adjustment and chain inspection, do a compression test. If compression is uneven, for example 380PSI on one cylinder and then other is 300PSI, that engine is worn and is never going to idle smooth again until you rebuild it.
In fact, a valve adjustment and compression test are the first thing you have to do before spending any money on one of these engines. If compression is even, then your problem is most likely an injection problem.
Just for your information, replacing the rack damper bolt on my car made a lot of difference, not perfect, but much better. Still needs further adjustment since I adjusted it very conservatively. You can try that as well, specially if you have the silver version. For 36 dollars and half hour of your time, you don’t have much to lose.
I know this is frustrating, especially if you are trying to keep the diagnosis and repair cost low by doing it your self, but I think there are a few things left on the list that you can do for not that much money before throwing the towel or paying and injection shop to fix it.