Budget custom 4-2 exhaust options

Hey all, looking to replace my stock exhaust on my 81 CSR for something a bit louder, but retains the 4-2 look and won't break the bank. I've looked around but have had a hard time finding a reasonable priced set of aftermarket 4-2 headers. Was wondering if anyone knew the compatibility of older stock exhaust systems to an 81. I know the part numbers are different, but was toying with this

this 1978 header on Ebay

since it's been cut right after the collectors, and then just mounting either pipe turn outs with an inline baffle, or some Emgo cone pipes. Has anyone done something similar or see this as a viable option? Any other ideas are welcome as well.

Any pipes that fit a kz650/750 will fit your engine, problems arise with the rear mounts, but you can usually find a simple solution 

No eBay APP ID and/or Cert ID defined in Kunena configurationI finally just purchased these this morning.  $150. Old American stock S&S headers made in California. I have been looking at them for 6 months. Something I can work with. I am modifying a set of Delkivic stainless header pipes to hug the bottom of frame, as I don't have much ground clearance. 
And get this! I am going to cut off about 3"-4-5" off of the back megaphone to suit my taste. Have to see how they look mounted to the stock frame mounts on a 76 kz900 frame.

Another possible option is to get the exhaust manifold from a ZN700. The KZ700 & KZ750-L3 have a similar manifold, but the ZN mufflers are usually easier to find on EB. The ZN came stock with clamp-on mufflers as do the other two models mentioned, and the #2 & #3 exhaust pipes are the same as the 650-CSR.  The 91-93 Zephyr ZR750 also had a similar manifold.

Here's a nos ZN700 manifold I sold a long while ago. notice that it has the same type of welded-on exhaust tip flanges as the csr. 
With those 78 headers in your EB link, you'll need the 78 half-moon exhaust collars as the csr collars are too short.

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