Lost GC, where to get a temporary Passport Stamp?

[WaitingGC03]

Hi, I lost my GC overseas and already applied for a replacement card thru I-90 application.

Where can I get a temporary I-551 (?) passport stamp in case I need to travel overseas before the actual card arrives?

The officers are the USCIS office at Newark (infopass appointment) told me this.

Thanks in advance.