Ohlins has a some dampers that are suitable for the 200. The TTX44 is a sweet high tech damper, 2.25" body, 4 way adjustable on the vehicle. It works on positive pressure, so it's cavitation free, but very expensive. It is designed/manufactured for off road applications, dirt bikes and FIA WRC Rally cars seem to be primary market. The particular unit I have here is used on the rear of WRC Subaru cars (yes the factory backed cars). They are designed to be very adaptable to a variety of applications, so it was fairly easy to build the parts required to mate it to the 200/Tundra chassis. It has a Progressive Dampening System, which is essentially a secondary suspension (bump stop). Ohlins also just released a TTX50, but it's not available for us little guys, yet.
Here is ORQ50 18/50, it is a 2.25" conventional mono tube type damper, also with the PDS. While less expensive than the TTX, it is still more expensive than comparable 2.5" units from King. It is fully adjustable on the vehicle. Not shown in the below picture are the sealed heim joints.
Arguably the best builder of larger dampers in the USA, King needs no introduction around here. They produce a bolt in shock for the 200. It is available with compression adjustment only. With a little work, the Internal ByPass option, which will function similarly to the PDS, might work here. Below, on the left, we have a King OEM bolt in. Next to it, one moddified to use the IBP. Cost is significantly less than Ohlins.
This photo shows the compression dual piston IBP feature along with the compression adjuster.
Here is King's page showing the compression adjust and IBP
So right now, the thinking is some 17" TRD wheels with 33.3" 255/80R17 BFG KM2 tires might(?) sneak into the wheel wells despite the increased track width. There are a handful 17" wheels that will allow the larger Tundra brakes to be utilized, the TRD units are on that list. The 255 will probably meet the grooving tool to improve their winter grip, and I might even find a way to pin/stud em'. The TRD wheels will painted black, gloss for easy wash winter durabilty, no beadlock rings.
Here's a silly one... I never cared for the small outer hub bore on the TRD 17" wheels... quite displeasing to my eyes as it gives the impression of a tiny weak hub and bearing assembly. Toyota always uses large diameter hub centers for strength, and thus the wheel bore is large to accommodate. Having gone to a semi-float unit bearing, the large bore is not required to run through, yuck. Problem solved... wheels bored and nice OEM Toyota metal cap finishes it off.
Those skinny's should serve you well on those crazy winters and windy, hilly roads up there. All I remember about the winters up there is constantly shoveling snow. That and discovering that my brake lines where frozen as I was sliding down a steep hill.
I'd be curious to see how the skinny's look on such a big vehicle.