Greater Anglia had no 102xx vehicles at the end of Mk3 service, most were converted to 104xx miniature buffet vehicles. If you work out what they became you should be able to locate them, for example:
10200 is now 10411 with LSL
10203 is now 10412 at Northampton and Lamport
10216 is now 10414 at Mid Norfolk
10228 is now 10416 with LSL
This link will give you some current numbers
10401 converted from Mk3a TSO 12168 10402 converted from Mk3a TSO 12010 10403 converted from Mk3a TSO 12135 10404 converted from Mk3a TSO 12068 10405 converted from Mk3a TSO 12157 10406 converted...
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