The 2a has a Series 3 dash,probably a Series 3 bulkhead to match, not a problem if you'e not looking for originality.
I did a DVLA check of the military one as it made me curious, the first registration date is 1993, which is fine for a military as that wouldbe when it left military service, and gives the date of manufacture as 1985. I'm still curious, since they stopped building Series motors in 1983!