Well it may be ugly but its better than the ones available over here, i found loads of people asking for a circuit to do this but not many links to sites, I cant imagine there is no demand for this type of product, in fact reading the manual for the Texon they even provide a printable overley for your convienience.
There are plenty of people such as yourself who can do a little pic circuit with output to a display of some description and the maths is not too difficult for the program 50pulses=1rev for just a counter, introduce a clock and you have a tacho (not that simple i know) but it is for those people such as yourself and myself for that matter but an off the shelf solution would be better for the masses.