There's plenty of options out there from the likes of RaceChip, TDI tuning, DTUK or even ABT offer a box (if you're willing to spend €1900

).
Before the age old argument of tuning box vs remap starts, there are pros and cons to both. For you, the biggest pros for a box will be extra power and warranty retention, also flexibility if you opt for a box with Bluetooth connectivity.
These days the price difference between the two can be a little or a lot. You tend to find that locked ECUs warrant a much higher price to flash, either by being unlocked or once the protocol is released to flash via
OBD.
If I were in your situation, I'd 100% opt for a box from one of the names mentioned above. A code reader to check the ECU and clear any sporadic errors from the ECU occasionally would probably be a wise idea too.