If you are curious about recapping, including "restuffing," read this article:
http://antiqueradio.org/recap.htm
Meanwhile, please phone your service guy right now and tell him
not to use NOS caps from that period, whether wax paper, plastic coated paper, or whatever. They are all junk because moisture invisibly gets inside them over the years, whether or not they are used. Even if they test OK at the moment, they will not last under normal operating voltage.
The article shows the different types, but since you're not doing the work, that is mainly FYI for your curiosity. Just tell your guy to use
new caps. Whether you want to pay him extra to "restuff" the old cap shells with new ones is up to you. I wouldn't pay extra for that, personally. Once the chassis is back in the cabinet, you are not going to pull it out every time a visitor stops over. As for future value, I suspect a future owner would pay more for a set that has been restored responsibly, rather than patched together with unreliable NOS parts.
Phil Nelson