Sorry, I don't think it's possible to deliver caller ID to a station without ringing (unless you turn off all ring tones). You could do this with a CTI app such as Phone Manager or Call Viewer.
Having said that, you could cobble together a hardware-based solution: use an analog station port, we'll call it 1111 here, and make it part of the hunt group. Buy a caller ID box from WalMart or Hello Direct and put it on user's desk. Give user a station speed dial key to revers-transfer 1111 (4-1111 by default). When call rings the group the caller ID box will display number and user can press key to answer. Obviously could do something similar with low-end IP phone like 5304 instead of caller ID box.