Another option besides building your own or buying a new one made for your engine would be buying a used intake from a motorcycle salvage yard. I checked mine out and found they had like 10 huge boxes full of all kinds of used intakes they let me spend hours looking through. They were all priced at $5 bucks a piece and many would have fit my engine/carb perfectly with minimal mods like just oval shaping the mounting holes or slight port matching. (many were equiped with a small pulse fitting instaled that could either be capped off or useful for operating a pulse type fuel pump)