The Me 410 a-1 has bombs available without modification research.
Dont mention it, just take it and enjoy it
some are stock so dont worry
They are only SC50s so hardly ground breaking (what pun?).
But as far as grinding goes they are a god send as you can grab valuable RP by taking out targets of opportunity. I wish Gaijin would add similar small calibre start bombs to some of their other Gun attackers that currently lack them.