I grew up in Va Beach, and did a road trip most every weekend to go boating.
The closest rafting is definitely the James through Richmond. The closest real good rafting is the New river in WV, I think it's about 5 hours from Tidewater.
I'd plan your reunion on the New River, great camping and rafting to be had.
I don't know any options for renting a raft, but shoot me a PM if you want a contact for a guide up in WV who will do a pirate trip with you and your buds.