Balls, I was thinking ACT gauge for some reason!!
But defo for less than £10 for a lecky version, for between 50C and 110C, just do a ebay search, there is a nice luminous one for £13.9 delivered.
I have just bought a air temp LCD one, for £3.75, accurate to +/- 1C.
The sensors are supplied as matched(resistance) to the gauge.
If there is ANY doubt about the matrix change it before winter, if a 88 matrix, it will be improved as well.
tabetha