EXHAUSTED

[Bob]

I inadvertently put my finger through my rusty exhaust yesterday.
I took a gamble and picked up a second hand muffler for a good price.
In putting on the ?new? system, I discovered that the old muffler had some form of what looked like copper coated gasket, seals type things (sorry for the tech jargon) These were in the muffler were the header pipes and from the front and the ?y? pipe from the rear cylinder go into.
Question, do I need to replace these ?things? and if so what do I use.

[Lucky]

They are exhaust gaskets, they are still available from yamaha

[Bob]

Thanks Lucky    
Yamaha, bless their little hearts want $70 for the three gaskets, since I paid $60 for the muffler I'm not keen on paying more for the gaskets.
I was thinking of getting some copper pipe about the same size and putting a split down it to allow it to crimp over the header pipe. any thoughts on this idea?