I just purchased an Extended Warranty for my 1997 RT/10. The 3yr/36,000 Mile warranty went out about 7 months ago.
I called my local Dodge Dealership where I'm pretty good friends with the finance manager and they said they use a 3rd party company for all of their Extended Warranties if the car has previously lapsed in coverage.
In my case since i've had my Viper there a few times they made a call and i was able to purchase an Extended Warranty with Chryler backing it up instead of the 3rd party company.
I could have purchased an Extended Warranty for 3,4,5,6, or 7 years and Mileage of 50k, 60k, 75k, or 100k miles (in any combination). I had them quote me three prices:
5Yr/50k = $1530.00
6Yr/60K = $1750.00
7Yr/75K = $1900.00
I went ahead and purchased the $1900.00 Extended Warranty. It's great piece of mind.
BTW, they also said you will have to put your auto through their 27 point inspection and you will have to pay for anything that's wrong with the vehicle to meet their "Used Car" standards.
Once that's been completed, they will give you a certificate that 'certifies' your vehicle. With this certificate you can then contact their 3rd party company and discuss their warranty options.
Cross your fingers and hope you can get a Chrylser backed warranty.
Good Luck...