If you want the closeup with the background blurred you are going to need a 'Fast' lens I.e. something with a aperture of 2.8 or greater.
Best bet here is the Canon 80-200 2.8 used these are about 600-800 which I know is about twice your budget but is really the only type of lens which is capable of producing a shallow depth of field, Which is necessary for the type of photo you want to produce.
The consumer lenses have small maximum aperture which has two advantages for the average consumer 1 - small and light, 2 - large depth of field (area apparently in focus) at max aperture (lens opening)
Unfortunately #2 precludes the close up with background out of focus
Understand I am generalizing here so before the "pixel peepers" start yammering it is possible in SOME cases to take the kind of photo you want but it will be difficult and not yield the same result a fast lens at maximum aperture provides.
Also Camera bodies are transient a lens collection of quality lenses will usually stay with a photographer for a lifetime. It's the lenses which ACTUALLY make the image. The camera body simply records the image on film or a digital sensor.
Lenses are a long term investment, I have some favorites which have been overhauled 3-4 times over over the years because I like the images they create and there is no 'new' equivalent