I would calculate the costs of something like S3 versus buying five 4TB HDDs and running a network file server.
You're going to save a ton of money hosting this yourself. I would go with two used powerful desktop PCs. One as a DB server and the other as the file server.
Store the images on the file server and store the image's path in the database server.
But an object store may be more convenient overall.
When I did something similar, I did store embeddings and the image UUID in a table and my images in an object store with the same UUIDs as filenames. It was simpler to upload the images and put them available through a CDN.