A bus tour promoting two ballot measures that would green light Oregon’s first privately owned casino visited Roseburg on Wednesday to speak with business owners and spread goodwill. The Yes On 82-83 Committee is on a two-week tour rallying statewide support for a Portland-area casino, which would be larger than any of the nine tribal casinos in Oregon. The $300 million casino, dubbed by its Canadian developers as The Grange, would be east of Portland at a former dog racing track. Plans include 2,200 slot machines, 100 gaming tables, a concert hall, water park and farmers market. Developers estimate building …