Here are a few sweater options you could use to embroider your own sweater:
This sweater is available in lots of colors and sizes. Unfortunately not always available on Amazon with free shipping, but worth it in my opinion.
This is an oversized knit romper. Definitely a bit oversized, but I personally love that look. Available in multiple colors and sizes:
Another great quality sweater option linked here. Available in gray, beige, and pink - sizes 0-3 to 4T.
Learn how to embroider your own sweater with this Stitch Along tutorial!