Find another Deere dealer or learn to look up your own parts...
I agree with JDSeller. NH and Deere are about the only viable game in town anymore if you want parts support in a P/T forage harvester. Gehl made a good machine but good luck finding anything unless you want to drag every damn one of them home from all the local consignment auctions.
A Deere 3950 or 3970 would probably fit the bill depending on what kind of power you have to stick in front of it. Likewise a 790 or 900 NH would be the comparable models in their line. Even at that those are getting to be old machines today... I wouldn't go any older in either line personally.