It's worth as much as someone will pay, the market always dictates the price. I wouldn't value this box very highly, i imagine the sound is so so and build quality on the lower side. I would not pay more than 4-50 quid personally. I doubt it will go for much more than that.
A box which looks like a clone of a cheap unit usually going for about £40 (on ebay, if mint, when they sell) and missing two keys is worth at best a few bucks, at least to the selective eyes of experienced collectors -- the ones that are supposed to attend this site. So I should not even write the following. The fact is, it bothers me to se that so far MRmObile has posted thrice, always about the same box, directly or indirectly asking for its market value, directly or indirectly advertising it. I am not bothered neither by the fact that he may or may not be the ebay seller, nor that the forum rules are circumvented (not being a supporter, he couldn't sell until he reaches 250 points -- to date he has 1). If neither the mods nor the board are concerned, why should I? In fact, I am bothered by the boombox collector agony on stereo2go. Nobody seems to notice or care, and the new blood (new members, or old/new members, this apparently being the case) are more interested in getting information about value than in "making classical boomboxes happy again". (Classical boomboxes, what I am talking about? I wonder why I bother at all, if not even the logo shows the shade of one?)
I am fully interested in: "making classical boomboxes happy again" as I am patiently taking off the shelf the radios that I have bought in the past and servicing them and making the cassette decks work again as I continually wish to play my cassettes in all of the cassette radios I have and then selling them with the proof of them working via my youtube channel Cassette2go. In the years past I have bought and resold a few radios WITHOUT opening them and servicing them and or also knowing the issues of 'that' radio. Now I have will only sell via video. Value of a boombox ( For me ) is based upon what I paid for them back when. The highest price I have paid for singular box is about $2,200.00 and that box I have not un-wrapped from its shipping box yet based upon what was said in the listing but this is another story.
