I just bought 5 pairs of e-bay for 8.50 each all in, they've since raised the price to 9.99.
But there should be another company selling for around £8.50 all in from Guernsey I think, who I've bought from before.
Search by pice+p&p, then only in UK if you want reasonably quick delivery.
You'll see the hong kong ones for cheaper if you're prepared to wait a month or so.
They are sturdy, thick metal and will probably last long enough under casual use.
all the black style and the silver style are the same as the maplin ones and other places i've seen (silver). You get you measurement to within +-0.02mm which is excellent for casual use, you'll pay lot more to go to 3d.p. or to the screw gauge micrometers.