All object types and all behaviors get their own OID in order from 0 on.
The order of the object bar kind of shows what the order the OIDs will be a runtime, but no there is no way to set what the OID of an object type will be.
It's best to avoid using the oid to identify object types in a save file because oids are only guaranteed to be the same for that object type for the duration that the game is run.
What you can do when you save is ignore what the oid of the object is and use you own numbers:
Sprite -> 1
Sprite3 -> 703 ...
and when you load change from those values to what the OID of the object is:
if loadedValue == 1
then oidToUse = Sprite.OID
if loadedValue == 4
then oidToUse = Sprite2.OID
if loadedValue == 703
then oidToUse = Sprite3.OID
...and so on.