Hi Don and welcome aboard. I'm a newbie too, and have found these guys a
great help. Although I'm not using a set of K boat plans, I don't think any
thing is available as a "kit"
The guys just buy the steel from a supplier that's close by. I live in
Calif. and got the major hull parts from Texas. The cost was 1/3 of buying
them locally, and shipping was only $600 so it was a bargain.
Smaller parts I had made locally cost as much as the big parts!
I used two big tank heads, at 84 inch diameter, but the same
company will roll a tube as well. The name is "Fort Worth F&D Tank Head
Co."
If you google it you'll find their web site. I bought my parts a year
ago, and prices on everything have gone up, but they did a good job, and
again, it was the least expensive route for me. The main problem was they
don't sell to individuals, so you need some one with a re-sale license to
order them for you.
A word of caution here, don't tell them you're building a submarine. It
makes every thing so much more complicated. Just tell them it's a water tank
or something.
The stuff I had made locally was for windows and hatch ring. The Texas
outfit made two tank heads and a small dome for the hatch.
Here's a picture of the steel from Texas.
Frank D.