I bought a set of the Mitutoyo vernier calipers for about £35, from either farnell or CPC recently (can't remember which) recently. They're quite good if you can live with the 0.02mm "resolution" and reading a vernier scale. If you're considering the Mitutoyo digital ones that wraper linked, the 500-196-30, they're on Amazon for £77 at the moment with free shipping. The 500-196-20 are on there "reduced" from £120, but they're just last years model and the vendors are clearing stock. The 500-196-30 is the newest and I think they've reduced the MSRP, so don't get caught out thinking you're getting an upgrade for the same price if you see both somewhere and the old model has a big reduced sticker on it.