You’d think so, wouldn’t you? But it just isn’t the case.
For silicone hoses, I thought I’d be fine with buying a set for a hawkeye STI but alas - not all the hoses are used in a Forester, you do have to do a bit of mixing and matching.
Samco advertise only rad hoses for 1999-2001 Foresters on their catalogues - no doubt they took one look at the FSTI and decided that for the size of the market, it was far too much hassle to put together kits with the correct sizing. Have a look at some of the earlier links posted by others here, and you can see how much of a minefield it is.
Which brings me neatly to my original point. Just because there’s a dearth of off-the-shelf kits and items, doesn’t mean that there has to be a lack here as well. It’d be a massive undertaking, but all knowledge is power and can only serve to help everyone.
Regarding Samco hoses, (Which I used on all of my water cooled VW's) talk to the guys at Mann-Engineering.
In my case I ordered the Mishimoto 2015+ WRX kit, TWICE! I got a new complete kit when we did the motor swap and I was able to use the "left over" hoses for things like my Radium AOS connections, etc.
We have damn near identical motors so I new they should work.
The one thing I really rolled the dice on was my Perrin spherical PSRS caster bushings. After that I realized I could switch over to the WRX/STI Aluminum front A arms. (This was also suggested by the North American Superpro Rep.as they sell the arms with their bushings already installed) So far as I can tell there is no front swaybar crossover for the SJ Forester. Nor is one needed. End links can/should be upgraded. I personally settled on WhiteLines upgraded ones that looked like the same design as the OEM ones, but adjustable. While the Kartboys worked fine in the rear, on my stage 1 suspension setup, the fronts bushings got destroyed just from daily driving. I attempt to explain to people that they really shouldn't put a bigger swaybar in front. Some listen, some don't and attempt to tell me how great their car feels with a 27mm front swaybar and either an OEM or 20mm STI swap in back. Then they attempt to keep up with me on a twisty road. Where you will never hear my tires squeal, and if you are in the car with me you will never see the traction control lights come on. (I spent too much time riding on road race courses and supermoto to ever push it on the street.) Anyway... they can't keep up and their front end keeps sliding on corner entry and exit. For now I think if I did my stage 1 suspension over I may have removed the front swaybar and put the WRX/STI 20mm in the rear. However on my Mann springs the 20mm worked great the car handled exactly square on my stage 1 suspension I started to learn a bunch about crossover parts when I purchased my 99s. The first thing I said to myself on the first freeway onramp I took at speed was I have to get ride of the rear end body roll! And so I learned that the blob eyes sedan rear swaybar would fit, but not the wagon!
My point in this diatribe is I am in agreement that we should not only have "here is a part number from this that you can use for that", but maybe an info introduction in different sections. Explaining what where and why you should or shouldn't do certain things. And then installation how to's at the the end of the sections.
If someone wants to start design a layout/structure everyone interested in contributing can start getting their part numbers installation tips etc. And if we can't have a sticky in this forum I would be happy to host the database an website for free.