Press Fit 30 (PF30) is a SRAM-developed version of the BB30 system where the bearings are housed in press-in plastic cups, which are in turn pressed into the bottom bracket. So yes it is a 30mm axle system but also is a specific type of bottom bracket shell fitted to your frame
Gussets PF30 BB for £35 looked the quite reasonable, otherwise Chris King BB or Hope 46 BB are more expensive options. Ordered a hope myself, are they definitely say you can replace the bearings, & have a good following on their std BB
Edit: you can get external PF30 adapters from e-13 (iirc there another one too), these use a longer crank axle, so avoid for your SRAM crankset