With changing the whole turn signal in Cooper 1.4 produced in 2008 you’ll need to find factory dimensions. You have to look at requirements for W10B16A motor coded vehicles made in 2007. When driving MINI Cooper you surely need turn signals to work properly. You also need to ensure 21 W of power for cars produced in 2003. Nearly all turn light bulbs of MINI have requirements at 12 V of voltage. Turn lights in Cooper may accept just one base lamps - BA15S. Turn lights of MINI vehicles with 1.6 motor don’t need to be changed often.
So, choose only W3x16d base type bulbs for 2007 MINI Cooper and take into account purpose of lamp. Also note that 12 V shouldn’t be raised and more than 21 W capacity isn’t recommended. It will surely destroy the whole lamp in cars with 1.6 motor having model number W11B16A. But if the glass isn’t damaged in MINI Cooper turn lamp, replace the bulb only.