My advice is to take the amount of money the spouse will receive, and then shop for the cheapest life insurance policy that will meet that amount. If you can find one, buy it. Otherwise, relax, and pay your SBP payments.
Check out www.Elks4vets.org for more info.
Please correct me if I'm wrong, I know that rules change, but isn't SBP required in order for the spouse to maintain Tricare coverage? Seems short-sighted to prevent the spouse from receiving medical benefits in order to receive a slightly less expensive annuity.