If you're going to scrap it anyway, break a window, roll it out, put a really big lever across the steering wheel and yank it round with all your might to break the steering lock. Then get a scrapper to come and get it.
If you are going to strip for parts. Same process, but cover it with tarpaulins until all the bits you are going to remove are off.
If you intend to get a new key, you may be better off buying insurance for it, then leaving it 6 months, then calling the insurer and saying you have list your keys.
Alternatively, do the same with a banks key recovery service.