I've been very happy with my Phantom (original) drone but had an issue where the propellers were damaged.  I tried finding replacement parts and ordered "9450 Self-tightening Propeller Blades" after being told they were compatible with the Phantom.  They're not.  Well, they're half compatible.  The original Phantom's motors only have right-handed threaded axles.  The props don't have threads, a standard nut holds them in place.  Obviously I can't fly the drone with only two props.  I managed to find one seller in China who had two pairs of props left and I've purchased them, so hopefully the props are good and I can fly my drone again.  But I'm really worried that if anything happens, my $700 drone will be gounded beacuse I can't find a $7 part.

Does anybody still sell props for the original Phantom?  This is my preferred solution.

Would it be possible to retrofit the drone with a pair of left-handed threaded motors so that I could use the self-tightening props?  I'm a bit adverse to taking it apart and swapping out parts but if it's otherwise going to be grounded it's worth a shot.  

Any input is appriciated.

This may be difficult to find DJI specific ones given how old it is. You may need to look online for them or ones that are similar. The older Phantoms with that kind of configuation can use either 8" or 9" props. Alternatively, you may want to find some that fit the old E300 tuned propulsion system, as they used similar props at one point and the motors were similar to the P1s. I wouldn't use the self tightning ones since the threads aren't quite the same.