Brother HL-2130 Replacement Toner Cartridge

I'm looking for a cartridge for my printer.

The original part costs $70 at a local newsagent. I understand there are alternative products which may or may not work well with the printer. Read about the Protoner in a thread that's closed. Are they still the ones to get, if one wants to save some dough, without harming the machine?

Any comments appreciated!