Where are these kits available at

Here is a link to one of the makers of these kits. http://www.rpmmachine.com/scat-strok...365-500hp.html

I am not into these kits I prefer to buy my parts separate, this way I can pick and choose what I want to use for parts, but this adds cost to the build. I think the kits would be fine for what you are after, do some reading on them and what's offered in there kits. Ask lots of Q's and do lot's of research, there are some great books on building Mopars out there.

i have the how to rebuild your magnum V8 book but it is to just stock spec

I assume i would need to have a balanced kit?

What other places would you recommend to look?

The 408 kits aren't much more, why bother with the 365, from my limited knowledge and recent searches it seems that 408s are lower end torque motors also