No one, including Peavey, seems to know the exact number. I've been compiling serial numbers for about six years now. So far I have documented:
T-40s
400 total number of serial numbers collected
88 total number of owners identified
7 pre-production serial numbers collected
2 owners of pre-production T-40s
393 production serial numbers collected
86 owners of production T-40s
T-40FLs
5 total number of serial numbers collected
1 total number of owners identified
T-45s
25 total number of serial numbers collected
3 total number of owners identified
T-20s
47 total number of serial numbers collected
6 total number of owners identified
T-20FLs
2 total number of serial numbers collected
0 total number of owners identified
I have the same info for the rest of the T-Series guitars and a few other vintage Peavey guitars.