Bucket Seat 'Identification'?

['63MurderTruck]

I'd like to get some 'fitted' seat covers for these buckets seats, but I have no idea what they were originally in.

Does anyone recognize them?

I looked all over and underneath them, but can't find any I.D. numbers or any other way to identify them.

They are for my son's '63 Stepside. We're on a tight budget, so that's why I'm wanting to get seat covers and not go the reupholstering route.

Thanks in advance for any info you can provide...