Wow I'm surprised they are that expensive, I bought one used for 14k more than 1.5 years ago and they are still selling for similar price. Anyway your best option would be X3 pro, it has SD 860 and I saw them selling for around 10k.
You can try looking for a used k20 pro, I'm currently on Resurrection Remix ROM, but I have tried PE 13 and it is pretty snappy but many of my apps don't run on Android 13 so downgraded to RR.