I popped over to a Yamaha outlet in London where they have some really nice violins ready to go with what look like purpose-built amps. The violins start at 250 GBP , amp is another 200GBP, and they had a wireless unit from violin to amp that frees you from the cord, another 50GBP or so .
The pickups generally are built into the bridge for those; some violins had one in-bridge and one under-bridge pickup.
There are a bunch of music shops (wind-specialty, ancient-music specialty, etc) at one of which I found a headway amp, in this case its a piezo element looking a bit like a ‘V’ that folds into one of the notches in the bridge. That would set you back ~200GBP.
In keeping with the cutrate opensource vibe here, I decided to get some regular bridges and see how attaching a flat piezo element to it will do .
As detailed below I also have a contact pickup on the way from violectra (a uk electric violin shop) and so I should be able to carry out some comparisons.