Need help matching with a charcoal blazer

[Daseinflaw]

I found a vintage Kuppenheimer jacket in my closet that my grandfather gave to me some time ago. The problem is, I have no idea what to wear with it since I don't own the matching trousers. Can someone recommend the right color pants/shirt with this?
Thanks

 

[TRA8324]

I have a sportcoat like this in the same color. It can really go with just about anything. I wear it to work with lighter grey pants, navy, or khaki. I'll wear it out with dark jeans or a pair of white jeans/pants. I think some chocolate brown pants would look good as well, but I've never tried this.

 

[pvrhye]

Anything that isn't too similar will be fine. It's a very neutral palette.