+x+xCNC machining or waterjet cutting are both excellent ways of cutting carbon fibre sheet. Yours is a small component and so well within the scope of any small desktop CNC router so you might even find someone on this forum who would be willing to machine this for you.
If you get into the commercial world for this then the small size of the part (depending on how many pieces you need) might work against you because it could be such a small job as to be unattractive to most machine shops.
To be viable for either waterjet or CNC you'd want to 'paste up' multiple bases onto a larger sheet so that lots can be cut in one go. If you get quotes back that make you inhale sharply and this sort of work is something that you imagine needing again in the future then I'd suggest comparing the price (to contract the cutting) with the price of a cheap, small, desktop CNC; you might be surprised by how close they are.
Matt - many thanks. I did have a look at benchtop CNC machines after watching your excellent video but with the cutter they were a bit expensive. I will approach a couple of companies this week and get a feel as to the setup and cutting costs. Many thanks for your help - you are a great company!
You're very welcome. There are lots of options for CNC routers though, some starting from around £500 on ebay and the ones we've tried work very well; take a look at machines like the 60-40 (sometimes branded as CNC-EST); it's Chinese made and doesn't have the level of support of a machine like the Stepcraft but nonetheless is a great bit of kit. You can see us using one of those in this
video of CNC machining epoxy board.
The PCB cutter bits should be very inexpensive.