All types of crowns not the metallic ones, can fulfill ur needs. But when aesthetics are concerned Zirconia and All ceramics crowns are prefered. If u see the cost factor Zirconia and all ceramic crowns come on the higher side. Porcelain Crown are affordable and good but they have metal content in them. And regarding cost of the treatment it varies from clinic to clinic so definitive cost cant be calculated

If gaps are small you can check if veneers can be done instead of crowns as they are less invasive. In crowns your options will be zirconia or ceramic. Zirconia which is very aesthetic can cost between 15000-17000 per crown