I have to work daily in very formal circles and official events, and I strongly advice you to go for a straight smooth billiard. Color is not as important as shape. All straight smooth billiards are "classy", because they are classic. You bring the image of Faulkner, Cary Grant, Gregory Peck, Bing Crosby, Errol Flynn. The epitome of men elegance used straight billiard or canadian.
For your dinners, they have also other advantages: The pipe fits well in the inside pocket of the suit jacket (actually, if it has a pen pocket it's perfect). Another thing it's that you cannot expect to do a 1 hour pipe, even if they smoke. So a small bowl like the ones in billiards is just perfect.
Seriously: with a formal suit anything except a billiard looks clowny!
There is the trend to go for black and silver for "dressing" pipe, but I believe that that's trying too much; A good grain smooth glossy billiard is enough. I see this in Alpascia
Alpascia Cheap Billiard.
Smokingpipes has many in Peterson, Savinelli and Vauen...
This one, in its reddish tones is an elegant pipe that shows more personality than black/silver!
And for something more daring, this contemporary finish:
All, well under 100$, all class, IMNSHO