It is possible to purchase historically correct fabrics and patterns for making costumes at home to save the cost of the making. Stringent rules are followed both in design and in manner of wearing. This site is very informative and includes many photos of various costumes. Mine has the colors of the vested skirt transposed, with a blue vest and a rust skirt. Tuuteri Reputedly not entirely Finnish, this costume is among the most expensive.
Materials only are also available for much less.
I find these two particularly attractive. Recently, I came upon some beautiful old Finnish stamps that depict Finnish national costumes.