Look for a small sawmill. They tend to deal in more interesting stuff to order. The guy who mills our stuff keeps a certain amount of stock air-dried and can kiln dry to the required state and can get it re-profiled (own machine coming soon hopefully). Always got oak, know he still has one of our chestnuts, we have some elm due to be milled and a cherry stem if I can remember where I left it. All sorts can be found, even some baked alder which has gone like mahogany.
In summary, find a mobile/small saw miller, you may be surprised by what they have and the price, can have boards cut at whatever size you fancy to fit the hall best (did 9″ boards in a barn recently, lot less nailing).