Refer to the map in the Where to buy section to find where it usually occurs.
Get yourself a 13×8" 2-blade propeller (KAV50.2.1308E), a suitable prop bushing (KAV50.2.0810) and a spinner (KAV50.10.221).
Unscrew the spinner from the shaft and remove the original 3-blade propeller with just a few turns of a screwdriver and wrench.
To fit the prop perfectly, you will need a prop bushing. In this case, a 8/6mm from the set works perfectly. (Legends say that our ancestors used to fill the gap with clear tape. Not recommended.)
Make small incisions in the spinner to ensure zero contact between the prop's blades and the spinner after installation. Clean the cuts with a fine file.
Cover everything up by screwing in the modified spinner with the two screws included in the package.
Take your Norden out and carefully teach it new tricks. Really short starts, fully vertical climbs and even precision hovering. Make sure to replenish its energy regularly. It will get really thirsty.