Get yourself a new one, I think most of them have 80 channels now (2 banks of 40). If you get a US rig the channels will always sound off unless its been converted to the UK bands. This is possible, done it myself 15 years ago when I was on the CB in North London. It is illegal of course and if the radiocommunications agency spot it they will confiscate it and fine you more than the cost of a new rig ! I lost about £1000 of equipment and got a £500 fine 15 years ago !
SO BUY A NEW ONE !