It looks like what you have there is a "standard" Gillette Slim with some serious brassing on one of the silo doors (the one that is facing "up" in the picture). The nickel plating has worn off and the brass metal that the razor is constructed in is showng through.
I am no expert, but from what I have read brassing has no effect on the quality of the shave. If you bought it to use - rock on - so long as it is mechanically sound, you have bought a razor that people here swear by as their daily shaver for a good price. If you bought it as a collectible, then you got a fair price but don't expect to make any money on it.
Could be an Aristocrat Adjustable (basically a slim adjustable with gold plating). Looks like the plating is pretty heavily worn on this one...to the point where the underlying metal (brass?) is showing through.
Here's an Aristocrat Adjustable that I found today. http://badgerandblade.com/vb/showthread.php?t=182923&referrerid=31638
That is what differentiates them. The slim is silver, the Aristocrat is gold. If you look at the web site I linked in my previous post you can see the difference.
Is it possible to tell a regular slim from an Aristocrat adjustable other than the color?
I do not know of a way, as I think the only difference for those two is the color (plating).
Sometimes photos can be misleading and you wind up with a presentable razor after a good bath and a shine. Sometimes gunk and reflections can be masking something nice....time will tell.