Nobody responded so I did my own research and here's what I found.
I discovered that some people will tell you that if you have a "rescue" horse, they won't insure it.
"They (insurance company) do not offer a market for rescued horses even if you can provide a letter from veterinarian regarding horse's health. There are two issues with trying to insure a rescued horse: 1) It is hard to establish a value for mortality coverage (no bill of sale). 2) Lots of horses are rescued due to the fact that they are not treated well by their owners. Hence these horses may not be in good health and there is no medical history on them."
This person went on to tell me that he didn't know of any companies that didn't make this standard practice and that there aren't very many companies that offer equine insurance.
While he's correct, there aren't very many, it's wasn't right about it being the standard practice. In fact, I found out that the company that he was writing for doesn't even make it standard practice.
So, if you are interested in equine insurance, I found two good names out there and personally spoke with them. The first is Rich Maggard of West Coast Equine Insurance Services (Phone: (541) 504-8686). He gave me some very important information;
"The important elements to remember when insuring horses are;
*The horse(s) must have value, as the insurance companies strive to protect your investment. "Gift" horses or "free" horses pose a problem, and are generally not insurable. However, value can be established in several different ways such as initial adoption fees or purchase amount, the cost of commercial transportation at the time of purchase, and training put into the horse after acquistion. Show records or production records after acquisition will also be considered.
*All horses need to be sound and in good health. Horses in poor condition will need to be rehabbed before coverage can begin. If the horse has been owned for 30+ days, this can be verified by a "statement of health" completed by the owner. Horses owned less than 30 days, in poor condition, have any prior medical condition may be required to have a vet exam completed before binding.
*Owners of unregisted or grade horses are required to submit photos along with the application."
What that means is that Dusty is insurable even though he is a rescue, but I have to fill out a statement of health.
His worth has been determined by his adoption fee and the money that I've put into his training and that worth is what then determines the cost of his mortality insurance. Now for WCIS this also means that he has a certain amount of money that is automatically applied to emergency colic surgery that can then be built upon with Major Medical/Surgical insurance and because they use The Hartford, the Major Medical that you purchase isn't limited by the worth of your horse (evidently many insurers will say $10,000 but in the fine print it'll say "or the worth of your horse whichever is less") WCIS will insure your horse until the age 15.
The other place that I checked into was Fry's Equine Insurance (800-842-9021, http://www.FrysEquineInsurance.com). They will insure until the age of 20. If you opt to check into them, double check that the major medical that you are purchasing is not limited by the worth of your horse if that value is listed at less than the $10,000/$15,000 additional coverage you are purchasing.
Now, as for price. WAY more reasonable than expected. I pay more to insure a dog. My mortality insurance for Dusty is $86.00/year based on his worth of $2400 (adoption fee and training) and there is a minimum of $250/yr so I'm adding $10,000 major medical for $350. That is $436 for my peace of mind. If you opt to go with Fry's, their prices are very similar, you can pay in three installments, and they will insure until the age of 20 and that's something to definitely keep in mind even if the payout isn't as much.
Here's a link to a helpful article on insurance and some of the specifics regarding the prices:
www.equisearch.com/horses_care/farm_ranch/management/insure22227/I hope all of this is helpful to somebody.