it will cost you to find out if someone hasnt had the misfortune already
Factors such as the engine condition and the efficiency of the overall set-up will come in to it, one engine might live for 20k with 20psi, another might only manage 10k. A k03 turbo runs out of puff at anything over low 20's psi from what ive read anyway. Even a roller ball bearing GT25 is listed for 22psi maximum!?
If you find out post up the pics though, will be interesting to see!