Welcome! I too have only one fob at the moment, the only option is to purchase one from the main dealer. You cannot sync a new/used one sourced from elsewhere, not even a 'blank'
There are a number of points here that need clarity because quite a few of them are "urban myths"
100% compatible fobs are available for the P38 Range Rover
There are a few options available to cater for different situations, I'm sure that most members will agree that it is not a subject to be debated in depth on an open platform ( security risks).
We can offer assistance to any P38 owner, no matter what region of the world they are located.
I will only discuss the options via private message, even then anyone seeking info will first have to send a copy of a current logbook/ title document for the vehicle they are enquiring about.
Thing are getting easier & lost keys are not the disaster that a lot of people think. You don't need to take out a mortgage to pay for it & you don't need to rebuild half your car by fitting locks, clocks & BECM either.
unlike the info I see posted that Landrover will now only supply a replacement Key No.1, you can have any number of keys 1, 2, 3 or 4 from us
regards
Iain