I know I saw a vintage felt baby shoes pattern on e-bay a while back - it looked like they sell them regularly, and they were very cute - reminded me of the old Storkenworks leather shoes
Another option would be a kind of moccasin - I made my girls high-topped ones so I could strap them around the ankle, but you could probably come up with something more like a Robbeez. The best pattern to go by is the shape of your child's foot

