@JadedTact30, I have three suggestions as unfortunately there is no direct way to yield such a specific list other than typiing 'life insurance' in the company name.
In advance search, select FINANCIAL SERVICES as the Industry and INSURANCE & RISK MANAGEMENT as the subindustry. This is a broader list of all insurance companies.
Searching 'Life Insurance' in the title yields 550 results. Adding the Fortune 1,000 at a limiter yields 6 results.
Best bet is to on assemble a list on your own with company and and URL then upload the using advanced search to find contacts only at those companies. "Upload a .CSV file to search for multiple companies (Use this template to get started)". if you have a library card to your local library, you should search their business electronic resources database. You can use "ReferenceUSA Business Database" to search by SIC/NAISC Code to get even more specific. Search results can be exported from ReferenceUSA to csv/excel and then uploaded into Connect as listed above to build lists as well.