Hello! I have a 20-year old Vanguard (Desa) direct vent fireplace that was installed when my house was built. Now it has stopped working. One fireplace company told me it needs a new pilot head assembly, but since Vanguard is no longer in business, it can't locate a replacement part. Another company suggested trying to repair it with a universal pilot head assembly at an install and unit cost of $460 with no guarantee that it will work. The alternative is to replace my unit and mantel at a cost of $8,000. Any opinions on the chances of a universal unit working? Thank you very much for any feedback.