if it is the header pipe they are really quite easy to weld if the problem isn't widespread rot. i have on several 240 and 940 headers (essentially the same)
used a reciprocating saw and 24tpi blade to make a fine smooth cut on the long single sections and weld in a sleeve when i had stress fractures. simple holes or cracks are even easier to run a bead with an electrical welder.

if the problem is a crack where the 2 join to one a weld is also easy to do.

if you do not know how to weld call around shops that make custom exhaust systems or have pipe bending equipment and do welding. they can likely fix you up for small money fast.

the only time i will discard an original header outright is if it has generalized rot and widespread rust through weakness indicating severely thinned wall thickness.