Alf, a 1.0mm max capacity would be more than enough for you if its for measuring shavings :lol:
I spent about £80 on my 6" ones but I'm into model engineering as well so need the 0.005mm accuracy. Most of the cheapies seem to be 6" not 12". If its for measuring the width/thickness of timber then it will move more than the accuracy of the instrument, good steel rule will do.
I have a pair of 6 inch ones. They are very accurate. (I have a one inch and 2 inch and 3 inch standards to compare.) comes with 2 batteries and cost only $16. The 12" ones are about double this price. I don't know if they ship to your side of world or not. I have used mine a lot and they are holding up well. Here is the link http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=47257