Many bikes use a 6" diameter wheel, 3 or 4 inches wide, with a 5/8" diameter axle. Measure yours to be sure and then find some in the same size. You can get new ones right now. They won't look just like the old ones, but they will look nice and they'll work just fine. You can shop around for used wheels, but whatever you find will likely need some amount of restoration. New wheels come as a kit with fasteners and bearings included.
For new wheels I really like the Astro design. Tri-Star wheels are a bit less expensive, but not as attractive. Here is pricing from
hent.com. You'll find similar pricing from lots of vendors online, but Hent's level of service is well known and will be attested to by many people on this site.
Wheels