What current is "normal" for constant battery drain (not parasitic)

I’m having some problems with battery going dead sometimes, and I noticed that there are some small sparks after disconnecting the battery for a few seconds and then reconnecting again. It is not big current (I have to go check with multimeter but I think that it is no more than 500mA, and only initially, it is reduced later).

If everything is turned of, then how big current is to be expected for clock (analogue, car is produced in year 1990) and alarm, which would not be considered as parasitic drain? I’m thinking that anything more than 25mA should be considered an issue?