I too, have State Farm as my auto, home, and business insurer.
I checked with a few of the collector car insurers, and then took their quotes to my agent.
He was able to beat every other one, with only ONE provision.
I will need to get the car appraised for the agreed value dollar amount.
For the same information I used with all the others, he was able to nearly cut the lowest one in HALF.
The Malibu is scheduled to come off winter suspension April 1, so I have until then to get an appraisal.
I will follow up here on what else I come up with or find.