I have not seen one on UK ebay no.
I am getting this one soon though.
http://www.geocities.jp/kenjin_keyboard/UNI04C6.htm
You might have more luck on Japanese auction sites.
I've been looking for quite some time for an ISO layout (85 key) IBM Model M spacesaver and the only references I could find were about one produced by Unicomp, model # UNI04C6 (the same as in your link).
According to Jim Owens, which I contacted, they have been produced/converted between 2000 and 2003 and shipped only in the US English layout (the extra key is not used, it just duplicates the "|\" one).
Finding one for sale has been quite hard. Unicomp doesn't have any in stock and I've never spotted one on eBay. They seemed to appear from time to time on Yahoo Auctions Japan (once or twice a year) and I ended up buying the first one that appeared, through Crescent Shop.
Once I received it, I replaced the key tops with those from a donor 1391405 (full size Model M spanish layout) and "converted" it to a spanish localized IBM Model M space saver.
I've been quite happy with the result and it has been my primary board for some months, until it has been replaced by my actual favorite, the softer Cherry ErgoPlus.