B778 and B998

hi i need help finding a replacement or equivalent

for a pair of complamentary transistors (i think that they might be mosfets) that i blew on my car amp.

the only numbers on them are:

1) B778
903

2) B998
904

i've tried to researche them on net but i couldn't find
anything. Any help or info would be greatly appreciated

tnx.

in your search try 2SB778 and 2SB998. on transistors they some times drop the 2S