Given that the Silver Hand tabard wasn't a graphical update of an old model, and is readily available for any and all classes, not likely.You don't have to have completed the Shadowmourne quest chain yourself to get it, if you don't feel like investing the time...you just need to keep an eye on your local Auction House!They average somewhere around 200-250k on WrA, right now. Not too shabby for a unique model with an on-click effect (looks great if you macro it with Avenging Wrath)!
You do NOT need the mount. I just got the tabard by completing part 1 of the order hall campaign.
Where's the HD Tabard of the Ebon Blade?