do you have any idea how much it'll cost me to replace it or is it better to send it back to the manufacturer to be fixed or get a new one if its possible?
This is a common repair job, so just about any reputable shop should be able to do this - if not under warranty.
Parts costs vary widely from brand to brand, model number, and monitor size but generally run from $50 to $150 for both inverter and bulb. Labor charges should be no more than for 1 hour, 2 at the tops. To save on labor, there are many tutorials on line - but of course, if something goes wrong, you can only yell at yourself. If the shop messes up, they are responsible.