Is there such a thing as a 5000 stall converter that is streetable ?

If the definition of streetable is 'honest', then there is no 5000 stall c'ter that is streetable. A lot of slippage & heat generated below the stall speed. Quoted stall speeds are generic. The greater the tq produced by the engine, the higher the stall speed.
This just isn't true. You really need to read up on modern converter technology.