What size pot? Silver maples

I want a very shallow pot for my silver maple tree. I was thinking like 4 inches deep by 18 inches wide in a round pot would this be suitable for a finished bonsai of this maple? If not any help on specification would be great or a good source for this tree?

How big is the trunk. Also how tall and wide is it.

Posting a picture of the tree would be a big help in advising on a pot, but a 4-inch deep pot isn't that shallow unless this is a huge bonsai.

https://ibonsaiclub.forumotion.com/t243-tutorial-on-posting-pics

Mind if I ask where/what is Fancy farm?

From another of his posts in response to a similar question:

I live in west ky about an hour near Paducah kentucky

which makes him an almost neighbor (maybe 500 miles) to me.