I have for sale a Quasar 3145 Computer Temperature Data Logger + 1 sensor.
It is mounted in a small plastic project box with 3.5mm stereo jack for easy attachment of sensors . It wouldn't be hard to remove it from the box if you prefer.

more info here: http://www.quasarelectronics.com/3145.htm

20 inc postage
Nochex, Paypal, Cheque.