Are 4-stroke exhausts to expensive?

As a long time car restorer, I have been amazed, amused, and disgusted by the price of essentially a straight through muffler. Whether it's plain steel, ceramic coated, stainless, or titanium, I have found very little real technology compared to what's happened in the automotive world. Why someone has not applied noise canceling technology (ala Flowmaster) is beyond me, though I do realize a single cylinder engine behaves differently than a 4+ cylinder. Still, a complete, aluminunized, true dual exhaust that included 2 Flowmaster mufflers for my 1973 Z28 was less than $300. How these companies have the gall to charge $600+ for a simple one cylinder headpipe and muffler is beyond me. That people buy them is even more so (though I realize ego and bolt-on nature are factors).

Oh, and God bless the 2 stroke! I tried thumper and returned, as many have.

If i was in this situation i would rebuild the topend or do performance cams. You cant beat a cam for HP for the dollar spent.