Can this be repaired? Would it be worth fixing? It's a Bassani

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Wow that must be thin steel. My thoughts are if the rest of the pipe isn't like that the yes get a bend made up. Have the flange on the end to worry about though or could that be reused & welded on. Realy need to have the pipe on the bike to get the bend made right. My HT1 was very much like that & think i used an old RD350 header as a starting point, good solid pipe.

Try any race vehicle/ frame fabricators in your area. Drag cars , dirt/sprint cars , most of them fab headers for their cars. Thus they should have access to a box of miscellenous random pre-bent pieces. You might find a piece close to your needs for not alot of $$ without having to buy a whole box full.   

This will give you an idea of whether it's worth fixing or not.
Seems a good one isn't cheap anymore.
 
 

I almost think I can see a weld inside...  looks to me like they used a standard mandrel bent exhaust u-bend that was cut in half, rotated a bit, and welded back together.

 

Measure the size of the tube and the bend radius and you can probably buy a bend and remanufacture the whole head pipe pretty easy?

Yes there is ,i'd do it .
there's enough pipes out there to take a lump off one.
Are you welding it or taking to someone?
I crashed my Aprilia RSR 250 racing bike with kit pipes on.
I got them rebuilt . They were bent double and by that time irreplaceable .
Unless you knew what they were, you couldn't tell.
So yes Yamahahaha. have a do .