here is a pic of the flange that iam going to order, does anyone know if i need a gasket for this flange? or does it seal it self? and if there is a gasket where can i find one? or make it?

 

here is how i have always done it

make sure the flanges are straight and not warped from welding

spread a thin layer of red RTV or copper gasket maker on the flange. and clamp them down

in other words i dont use gaskets on many of my exhaust parts. no leaks for me on a v6 with 25 psi from a pt61 and a t76