What supplier for interior resto

I'd probably have an auto upholstery shop install the covers and put in new foam. It would be a custom job, not pre-formed, but they do that all the time. Understandably, it would be disappointing if you and your son were planning to do the job yourselves. Also, it would incur an unexpected expense. You could try to make your own. Look to see if you can find advice on how to do it.