I heard that a cheap one cost around $20-$30. But if you like, you can try to desaturate an image to about -50%. The image won't be the same as an IR, but you get a Black and white that is not totally black and white. example from one of my previous post:
The image above is taken at night without bright colours, maybe try this with an image with bright colours, may have a better effect. Other method will be colouring the photo using photoshop's airbrush and masks.... Hahhaha... can die... Dunnoe how airbrush artist do it ah....