I believe that it is a Bargman L 200 or so.... No longer in production, but found on other old trailer manufacturers as well. Hunt for one on all brands of old parts trailers you can find. You might get lucky. There are new old stock and reproductions available. Today, there are a half dozen for sale on eBay, which is a good place to find a replacement if yours doesn't function well. There is also a rebuild kit available.
If yours is working well, but has pits and peeling chrome, I'd lightly flap sand the surface smooth and rub in some chrome paint to into the pits to retard further surface deterioration, clean, lubricate, and reinstall it. Put it on your list of parts to lurk for, and maybe you'll find a nice original one for less than $400. By weight and size, it might be the most expensive replacement part on your entire trailer.
Hello, I don't know if this handle is correct for your 63, I have that handle on my 69 Trade Wind. To remove the handle you need to pull the pin that shows in your picture. I removed mine with a pair of dikes ( side cutters). As for the plateing, there is a place in Philly.They are on the internet. you send them the parts, then they give you an estamite, at that point you tell them yes or no, if no they send your parts back to you. That lock is not made any longer. They do turn up on e-bay now and then, but sell for around $400. I buy spares for parts when I find them cheap enough. good luck.
I can confirm that removing that perpendicular pin will allow you to slide the handle out of the outside plate. Take a pair of needle nose pliers to pull out.
I don't think for the looks of your priceless Bambi that you would want to spend a lot of money on re-chroming that lock. If you want a new one, send me a private message. I have lots of these locks new in the box and the Rebuild kits if you want to rebuild it.
Of course someones suggestion of sanding and using chrome paint is a much cheaper way to go as long as the lock functions. If you need help putting it back together I will help you with that. Attached is a pdf of the exploded view of the lock if you need that.