I used to run koni yellow with adjustable damping on my old volvo 850r and LOVED them, i called up koni directly and they informed me that they have no koni shocks that will fit the fzj80 series trucks.
They make shocks for the 80s, but unfortunately do not important them to the US. IRC we looked at doing a group buy several years ago and even then it would have been about $1000-1400 to get them after the exchange rates, import hassles, etc.
I am a big KONI fan as well and I run them on my Honda Civic race car. My company has an wholesale account with KONI NA. From what I gather they might be able to bring it in for us. Let me email my guy at KONI and see what he says.
Here is what I can find according to their website
Here is what I got from KONI. Looks like I will send Brian a PM soon
We brought in several sets of 90-5389 and 90-5390 for Jowett Engineering firstname.lastname@example.org at the end of 2010 to try to find a place in the US market for them. The 90 series Raids are really big, extremely robust units that are stronger than the other options as they are based on our heavy duty transit bus and bus sized motorhome shocks. They get used for a lot of the media and support vehicles that go along with the Paris-Dakar Rally racers and are used on some of the more production class Dakar race vehicles.
The 30 series Heavy track are much smaller and are normal sized shocks (50 mm OD bodied mono-tube)that are not for crazy hardcore off-roading but more mixed on and off-road duty like a normal performance truck shock. They will also be priced more like a normal shock as well. We have not ever imported the 30-1426s but did bring in some 30-1427s late last year that were exported to Ecuador.