I still think it will look good!! We'll never tell

It can still look good, strip it and paint it black!!!

Sorry to be the bearer, but now you know you have a unique old level. Bet you can never find another just like it. ;-)

I started to file and grind the end to match the other end, to be closer it would need  cast iron added. Even though I can weld cast iron  using cast iron rods (you don't see the difference in color) Probably not worth the time and effort. Still a ways to go, don't want to take too much off!

I've got a Stanley cast iron level that was similarly cut off.  I don't know if it lost an argument with the floor and was trimmed to get rid of the break, or if a previous owner needed a shorter level.  I've held on to it so I can salvage the vials, if ever I figure out how to remove those little setscrews, which have long since gotten married to the casting.

I just got one of the 3 screws out. a 50/50 mixture of atf (automatic transmission fluid and acetone works well) 2 more to go.
Just put a little drop or to on top of the screw and let it soak. Did that on the 6th, gave it another drop on the 7th, got one loose on the 8th. By the end of the week with a little luck all 3 will be out!
I mix up a batch  of atf/acetone and put it in  empty liquid wrench cans keep it in multiple places in the shop  so it easier to find one.

Known as JAFE Juice!

I found that soaking rusted parts in Coca Cola works quite well too.  I learned about this from guys getting a piston
freed up on old hit and miss engines.

I also told a friend about it when he was having no luck getting the breech plug out of a black powder rifle that someone had left loaded for years, he poured some coke down the barrel and the next day he easily pulled the breech plug out.

I do believe part of the process when removing rusted screws is having good luck.

I gotta like oldgoaly"s post re, fill mt cans and keep them in multiple places in the shop. You must be peaking in my shop windows.

I tried the coca-cola thing on some piston rings once, and all I got was sugar-coated pistons.  Vinegar for me.  Less sticky.