Mozart piano concertos orchestra only?

[jwchopin]

Where can I find recordings of an orchestra playing the Mozart Piano Concertos, but without the piano part? I know about MMO, but they only have the really popular concertos, yet I am learning the second movement of the fourth concerto, a very unpopular one.

This would be my first concerto as it is probably the easiest out of all the piano concertos and I would like to hear myself with an orchestra.