I created a cable myself, i just bought the cheapest USB > Serial cable i could find from eBay, together with some RJ11 connectors.
Cut off the default connectors that were attached to the wires and crimped the connector to the USB>Serial cable (pinout can be found here: http://gejanssen.com/howto/Slimme-meter ... pinout.png) and you are done.
Ofcourse you also need an RJ11 crimping tool (mine is a combined RJ45/RJ11 crimping tool) but maybe your neighbour has it

My cable has the Winchiphead HL-340 chip, and is detected fine by the Domoticz Raspberry image. My meter is a Kaifa MA105 (DSMR4 115200 baud, 8N1 with inverted data). The HL-340 chip automatically re-inverts the data to normal. Pay attention to which chip your cable has, the cables with PL2303 are advertised a lot, but they don't automatically invert the data. FTDI is the best, but also the most expensive compared to the others. HL-340 also works fine. For the PL2303 you need extra hardware (transistor + resistor) to re-invert the datasignal.
The colored rings of the resistor translate the value: http://www.weerstandcalculator.nl/
brown - black - orange - gold = 10K / 10 kilo Ohm
In the diagram an Arduino is shown, but you need to connect it like this:
- the line shown in yellow to the 'Rx' pin of the PL2303 board
- the line shown in red to the +5V line of the PL2303 board, can also be marked as Vcc / Vdd
- the line shown in blue to the ground (GND) of the PL2303 board
I think this approach will work for 90% of the modern Dutch smart meters, and will cost you no more than 3 - 4 euro. Only need to wait 2 weeks for the parts to arrive from China

Only for some Landis & Gyr meters it is sometimes a bit problematic to read their data, but i already saw a topic somewhere here on this forum that somebody got it working by adding an extra resistor.
Oh and if you bought a very cheap cable with an FTDI chip, pay attention as it might be a fake chip and it could be bricked by when you connect it to a Windows PC (due to a Windows update that contains a driver that will brick fake cables) Search for #FTDIgate