I have had a look for the registered design number, thinking that it would give some clues.
The database at the IPO is only useful for current designs, but the National Archives holds most of the older records.
The entry here:
http://discovery.nationalarchives.gov.uk/details/r/C1741169 shows that RD 664709 was in a range of numbers used between 1914 and 1919, suggesting that the
earliest possible date would be somewhere in that range. (It does not give the design registration itself, which has not been digitised.)
Looking at vices in a 1925 Melhuish catalogue I found an entry showing a vice just about readable as having that number and the Record name on it, which confirms that the design had reached the market place by then.
Of course, the Record designs continued to be made for many decades. At some time, we know that the design must have changed from your pattern, with the RD number across the top, to the later pattern with the model number much larger, as shown here
https://www.flickr.com/photos/35604059@N03/4651253942/in/photostream/.
So when did that change happen? I don't have a full set of Record catalogues but I do have a general tool catalogue from Gardiner's of Bristol in 1940 which shows your pattern. I also have a 1957 Tyzack catalogue which shows the later pattern without the RD number. So, on the evidence so far, your vice could be between 1914 and 1957. Not an exact answer, but a bit closer than "quite old" which would have been my first answer!
(I do realise that catalogue pictures were a sort of general purpose library of images, and not 100% accurate representation of what was actually offered for sale, but at this distance they are probably a good enough indicator for most of us.)