What Aspenshaw says is spot on,
No sense in buying just because the dealer is nearest too you. He may only have a limited selection of models. Even worse, if there is insufficient trade in the area, the dealers long term viability would be risky (& your warranty cover) . Then you finish up travelling much further afield to find A.N.Other dealer who covers your motorhome.
I think you may have to accept that it appears there is insufficient trade for a dealer to justify opening a sales unit in the vicinity.
Search for the make, layout, style of motorhome / campervan & budget