Sam, sounds like you're looking for a spectrophotometer. These are (you're right) expensive instruments from companies such as Barbieri, Konica-Minolta and X-Rite.

The instruments sold solely for calibrating monitors are usually, but not always, colorimeters, which are less expensive.

A spectrophotometer can measure across a range of colour temperatures and into the near-UV. Most if not all need to be in contact with the sample to read its colour accurately.

Spectrophotometes are used for all sorts of purposes in medical research, industrial applications, cosmetics, etc. etc. but you're looking for one intended for printers and / or photographers, something like an X-Rite i1Pro (if you see one of these with 'Macbeth' or 'Gretag-Macbeth' instead of 'X-Rite' as the manufacturer they will be ancient and knackered).

I just checked on ebay (UK) and it looks like a 2nd generation i1Pro will set you back around £400 - £500, but make sure you get the software and the dongle if you're tempted! And don't forget, an i1 Display is a colorimeter, not a spectrophotomete.

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