Or if you want to save some $$$, you can make your own bleeder with some PVC pipe and brass fittings. At least on the Birels we’ve owned, there is a 1/8″ pipe thread fitting on top of the master cylinder, so standard 1/8″ brass pipe works well. Figure a 6-10″ piece, then a brass valve, then another 4-6″ of brass pipe. That attaches to a 8-10″ piece of 1″ or so PVC pipe. Screw the whole thing into the fitting on the master cylinder, fill the PVC with brake fluid, and open the valve. Then open the bleeder screws on the caliper (typically one on each side) and let gravity do the work (that’s why you want the bleeder unit to be fairly tall). Or you can press the brake pedal, open the bleeder, flush, and then close the bleeder without releasing the brake pedal. Faster, but slightly trickier.
Our birels had a simple Allen screw for the bleeders, whereas our Arrow has automotive style bleeders. (Actually the bleeder isn’t needed with the Arrow, since it has a reasonably large–by kart standards–fluid reservoir). I’d guess $10-15 at Home Depot