Yes. White crowns for primary teeth are available. There are different alternatives including cost effective ones like polycarbonate ones. However they are a little more difficult to place and may not last as long. Ask your dentist what they have available.
Costly investment. I have had parents foot the bill for the expense of a single porcelain tooth, a central incisor, for cosmetic reasons. The idea of putting that investment into kids who often need 8-12 caps on teeth that are shed is a bit much. The position in the gum line needs to be preserved to allow space for emerging permanent teeth or some would just toss the decayed teeth & be done.
Yes. A few companies have begun producing zirconium crowns. These are made from a strong white porcelain. They are more costly than the stainless steel crowns but not as expensive as custom porcelain. Ask your dentist if they use ez pedo or nu-smile crowns.