'New' could be a relative term.., lol, i.e., my '89 is new to me, and between 'new' used parts, and 'new' parts, i.e., OEM, and aftermarket.., lol, it is approaching a different 'new'.
OMIX-ADA is one place I have ordered from, and although they 'claim' to have tested many of their thousands of parts, it's hard to determine what is made where if that is a concern of yours. I have their hard copy catalog, (no pricings--just part numbers), there are no absolute determinations as to where the parts are made, nor any definative information as to quality. Since they have a section in their catalog showing a picture of 'XJ's in various parts-crates, alleged to be OEM, there can be an eluded sense that most of their parts are American OEM. Guess what.., many of their parts are OEM, but Chinese OEM since they've been making XJ's since 1984. If the part can do the job.., you get what you can get.
RockAuto is another place I've gotten parts for several vehicles. One surprise was when I got an entire front hub assembly for a '74 Buick Apollo. Made in the bad old commie china.
For my current newly acquired '89 XJ, I have gotten parts from many places. One I would recommend for the part you are looking for, lol, comes attached with another part, i.e., the entire track bar. Might add that it is a hundred bucks more than so-called OEM, but 'ya gets what you pay for. Me, the XJ went into a reverse speed bump, i.e., a hidden frozen trench under water, and mud, and the hit was severe enough to 'blow-out' the zert in the track bar at the top end. It was a Chrysler OEM part, now dead enough due to it's contribution to "DEATH-WOBBLE", to cause me to read up on the problem. Here at

, found references that led me to:
http://www.kevinsoffroad.com/cart/index.php?main_page=product_info&cPath=2_6_33&products_id=1017
If you are going to spend the time changing out parts, consider using H.D. parts. Me, I hate doing things twice, or thrice times.
Too.., you can probably get an undamaged 'new' OEM part at your local junk yard.., just a little more upfront guess-work.

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