You can either do the same, or you can get a replacement logbook issued. Is the number on your cage still legible? Do you remember who issued it? If the number starts with a "22" then it's someone in NER. With that number I think they can re-issue a new logbook with the same number, and the same original issuance date. That is important for grandfathering in your cage for the rules that were new in '09. Your car will have to go through a full annual re-inspection, and that logbook can be re-issued.
If you get a NEW logbook issued (with a new number) then you're going to have to conform to all the current rollcage requirements.
Maybe for this weekend, you show up and do the same thing as you did at the Glen? Since this is not an NER event it may be easier that way. Then we can coordinate getting the old logbook number re-issued over the Winter.