Those hedman headers are no joy to change gaskets...just sayin...I have them in my 72 Scamp and while they do fit and you can cobble together some pipes between a mini starter and the T bars, if that gasket blows out, you'll need stubby wrenches.
The money I spent buying mandrel bent sections and having it fabbed in wound up costing basically the same amount as a set of long tubes from either Doug's or TTI..