Thanks again all, fair bit more than I was hoping to spend, but you do get what you pay for. Might see if I can borrow one from work to ensure it's a good one and calibrated correctly.
I did like the look of the Parkside torque wrench sold in Lidl's which I think goes from 80-210 Nm.
Always tempting! However I bought a set of Parkside TX keys from Lidl, but the one I needed was slightly oversized compared to the screw I needed to undo...