Stock H1s are not going to work with the stock steering locations unless you run spacers or recenter them. Neither of which I wanted to do or did.
As for the plans for the steering arms... there isn't any real official drawings of them. I've got a few sketches on some paper and those plywood mockups. I could quickly dimension it all out for you if you needed and send it your way if you are truly interested. Let me know and I'll get on that sometime this weekend.
For the cost of the steering arms, I couldn't even throw a guess. Of course I didn't pay for my labor and I got the 4140 alloy steel relatively cheap (which is really overkill, 1020 or 1018 would probably be fine).
The above being said, you can purchase high steer arms from a few companies that are already offset for the H1s. I didn't do that for a few reasons.
First, most of the ones that I would have been able to afford all retain the use of the stock cap. If you look closely at the cap you'll see that it has a pretty decent fillet around the edge of the spring retainer before it gets tot he cap bolts. I didn't like the fact that the inside of the arm would have to get radius'd to clear those as in my opinion it makes for a kind of weak setup.
Secondly, most of the arms are only 3/4 or 1" thick and do not have an angle on the end to correct for the proper alignment of the joints. Sure, I could have added it myself, but at the 9degrees it takes to correct the angle the material thickness drops almost 1/4". I didn't feel that 1/2" (starting with 3/4") or 3/4" (starting with 1") was enough. It probably is, but I just didn't want it if I was going to be using a 3/4" bolt. By starting with the 1-1/4" material that I did I was able to retain just over 1" at the end after the corrected angle where the bolt goes through.
Third, I just plain enjoyed making them!
Sorry for the long winded post, I probably have to much thought into it.
Again, let me know if you want me to create quick drawing for you with dimensions and I'll do it.
(For those that don't have any clue what either of us are referring to,
go here)