We've already talked about Bernard and Ned! Happy thread them! Whenever :D

I also potentially have Thaddeus Flint (Currently looking like a Fisk) he is the Master of The Flint Institute of Advanced Magic - where people can come for basically magical university. It's relatively new so Ned wouldn't have gone but he could consider taking a course to improve his career prospects or to become an animagus or something.

He is also a senior member of the Knights of Walpurgis, which is a basically a free masonry style organisation which his father may have been part of, which would give him an invite to join as well or he could wangle an invite. It might be something he thinks would help him with his ambitions and get him into the same social circles of other wealthy and powerful pureblood families as it is exclusively for the advancement of purebloods.

I have Murdock Greyback who is head of the DMLE, he is rather stand offish unless he really knows you, but they would come into contact professionally.