I'm not sure (I think others will be able to clarify) but you might be able to send this back to Microsoft for a free replacement if it's under warranty. I certainly saw the option for screen crack issues when I was in the process of sending mine back. Have a look here... http://myservice.surface.com
As for 'buying a new LCD' I wouldn't think you'd have much luck repairing it yourself. Have a look at the 'tear down' on iFixIt... very hard to do things like that unfortunately.