Hi Mindy
Jerome is correct!
What you need is a pair of 1940 to 1948 Ford steel wheels if your bolt pattern is 5 on 5 1/2".
But if your bolt pattern is 5 on 4 1/2" you can use Chrysler, Plymouth, Dodge wheels 1941 to 1948, they are also 16".
Made for 600 x 16 tires......and have the correct look for the era of your trailer.
If you want new wheels you can get any size you want from either Wheels Vintiques or Early Wheel Co. and they are very cheap.
I had them make them for Miss Piggy (with my specific offset) for $60.00 ea.
Personally I like Artillery Wheels (which I purchased from Wheels Vintiques) 15" and purchase White Wall radials.
This, with my Dexter allows me to tow at any speed I want!
Please feel free to contact me if you need help with this, as I have some cool stuff in stock?
Good Roads
Brian & Sandi