Typically, insurance companies do want your supporting business to write the coverage on the RV. Just be sure whatever carrier you use provides coverages comensurate with RV usage.....loss of use, motel costs if you are on the road, broad road service coverages, etc. I know Progressive provides a great RV policy, but it sounds like they are much more expensive in Oklahoma. I use Safeco Insurance in California....they are now owned by Liberty Mutual, and I don't know if they do business in Oklahoma under Safeco, or Liberty Mutual. They provide a very broad RV coverage....unlimited towing, loss of use, etc. I pay about $850 per year for my Newell. Here is a website where you can get some other suggestions:
http://gypsyjournal.net/blog/ I'm sure Nick will also have some suggestions.