Frank
As Paul says no reason at all why it would not work.
Noise - I doubt it will be that different to twin pipes. The note might change though due to gas flow through the hole being doubled.
Restriction - Will probably perform much like stock.
A decent tune will help though a Triumph TORS tune would certainly do for now.
I know Dave Platt's stuff is not "Chinese e-Bay" cheap - but he has what you want - I'm pretty sure of it.
What is the aim of the swap?
1)Be different.
2)Power
3)Noise
4)Aesthetics
When you have that list ordered the final answer becomes much much simpler.
Just doing things on cost alone is only really a go if you can fabricate yourself.
If POWER is anywhere on the list btw - Change the **** headers.
I have a simple pipe similar to this here sat in a box.
CAFE RACER GRAND PRIX STYLE STAINLESS STEEL EXHAUST WITH SEPARATE BRACKET - Cafe Racer Seats
If you are going to do a 3 into 1 - do it!.
Oh and
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