The Dwarf Car was originally developed by Ernie Adams. John Cain (Dwarf Car Co., AZ) and Ernie turned the whole deal in to a race car thing. Elliot Forbes-Robinson and Humpy Wheeler took that idea and put fenders and runningboards on it and standardized rules (hence, spec designation on the Legends Cars).
Kind of a toss up on brakes, depending who you talk to. There are more aggressive pads available through several, manufacturers. Whole thing started off with stock Toyota front disc brakes and stock drum brakes for the rear. Dwarf Cars have run the same Wilwood calipers that INEX is calling "New" and four wheel discs for all four wheels for years. I recently picked up a set for cheap (new). Wilwood sells the same caliper for $89.00 each.
SCCA allows Hoosier and GoodYear slicks for some of their racing division. See current SCCA rules. I have also gotten reports over the past few years from several Legends Car drivers that run SCCA, that they are allowed these slicks. As far as I know, BFG's and Federals are also allowed.
I like the advice about buying used to start out. One never knows if they will like this type of car. Also, used cars tend to come with spares. Always a plus!
My 2 cents for what it's worth.
Steve