bmw 320 i

[seraphim nichols]

hello
i am new to the forum.
my friend gave me his 83 320i. it needs a bit of work. I know very little about these cars other than i would like to restore this car.
firstly- it has no muffler. nothing from the flange back. this is the last flange...off the middle section.
it does not have hangers, etc. all missing
a muffler locally would cost me $108.00 w/o hanger hardware.
i could get a muffler online for $60.00 and a hanger package for $25.00.
is there any reason why a person couldn't get flexible tubing, a high performance muffler, and install this?
does it need to be a rated muffler for this particular car?
what are my options?
thank you

[NSX-R-SSJ20K]

why aren't you asking this in the god damn BMW forum?