Those scratches cannot be taken out using WD-40. It's a very good cleaner and lubricant, but is not a magic panacea for fixing paint scratches.
You may be able to take it to a body shop where they would have to strip the bumper and repaint it (could possibly blend the area through sanding and repaint as well). They'd have to make the call on that.
If the scratches are too deep, you may end up having to purchase a new front cover and have it painted. With the prices of these lately, this may be the better and cheaper option overall, depending on the amount of time it would take to recondition yours. I'm sure the body shop will tell you which is the better option cost wise, especially if you come to them with cash (not using your insurance company).
If you are handy, replacing the cover shouldn't be too difficult. You could buy a new one yourself, get it painted, then replace the old one.
For any of these three options, I would think you could get it done for under a $1000 (at least here in the States) ... especially if doing the last option. I recently had to replace the one on my Mother-In-Law's car. It was far less than $1000 to do and the color match was perfect. This is subjective though, so may be different in your area. The only way to know is to get a quote from your body shop (or a couple, for that matter).