Front Left Sway Bar Link

Are you sure it is the sway bar you are looking at? Sway bars are bent to start with to do their jobs so the left end will be a mirror to the right end. So by 'bent' I'm assuming you mean one side isn't a mirror to the other.
Most sway bars are mounted with 6 bolts. 1 bolt at each end at each hub and two on each U clamp holding the sway bar bushes in place. Sway bars need to flex and bend to do their job so they shouldn't be welded in place.
Could you comment below with photos of the part your looking at and where it is on the vehicle?
On some vehicles you'll need to lower the front sub frame to get the actual sway bar out so it's often a job you can't really do on you drive.
Comment below with more information and I'll try to help you more.

German specs are what I use and they work perfectly...
it's; GOOT UND TYTE.

That noise would be the sway bar links, the ball joints in them are worn out most likely to torn grease boots. Watch the video. It is an 07 but should be the same procedure. How To Replace Front Sway Bar Links On Nissan Sentra

I have 2003 one problem is sway bar and I do see on others broken mine has left the side.

A sway bar is a suspension piece that keeps the left and right side of vehicle connected to help with turns. They are held together through sway bar links at each end, which are fairly common to break or rattle over bumps.

Your old sway bar made of tubular steel. New sway bar made from solid steel. You have a frame under engine the sway bar attaches too. This frame also supports your engine and trans mounts. Follow frame and there are 4 bolts securing same. Mechanic I watched supported engine underneath. Loosen back bolts though not removed. (please note sway bar has arrow that bar can only go in one direction) This maybe your problem. Attach bar to frame and fitting's. Best if you raise front end and remove both tires. Good luck

yes they are the same. 8 months sounds premature, but if it was an inexpensive brand X part they used it is possible.

It could be a worn or broken sway bar link or sway bar bushing. Inspect all the suspension parts such as the steering linkage just to be safe, but pay attention to the sway bar system. Mainly the bushing and replace any that is damaged or worn with urethane bushings, they cost a bit more but last a life time of the car. Good luck and hope this helps.

my opinion would not to muck about with things like that and replace it with genuine parts that way you know it's ganna last price not sure but would not reconmend welding it don't play with your life when it could only cost like 300 to 400 to save your life

The sway bar bushings are under the large clamps that hold the bar to the frame. The ends of the sway bar are connected to the struts by the sway bar links. When the links wear out, they clunk--not squeak. The bushings are under the retainer in the pic below.