Engstrom JE 1874

[SlickWillyTFCF]

Hi Gents,
It's been a while since I've been on here, still trying to perfect the shave. I have a question that hopefully has an easy solution. A family member gave me a Johan Engstrom JE 1874 razor that came over to the states from Norway with the family a few generations ago. It was cool to find it in the database and see how old it is, but it needs some work. There doesn't seem to be too much pitting and only a small amount of rust-ish grime and whatnot. My question is: what's the best way to clean the grimy rust stuff and make sure the arrow design on the blade doesn't get removed? I've cleaned up a few internet specials and with the amount of sanding they needed I know that route isn't the best option for this new addition to the collection. Any help would be appreciated.

EDIT: Nearly forgot, what would an average value on this razor be?