Have a look at the link below, they sell deactivated Thompsons. http://www.rytonarms.co.uk/site/home.php
A neutralized Thompson would cost you about 450 euros (that's what this one cost, but that was a few years ago, so I figure you'd pay a little more now, it all depends who you buy it from.) Don't know about the replica. A M1 garand replica would be about 200.