If your engine has not been convert to breaker less ( meaning points being removed) the part number you need is 298968. If you have a breaker less or want to convert to breaker less the part number is 398811. As I am not is the shop for over a week, I would double check these numbers with your local repair shop.
An 80 model could still have points but any small repair shop should have a bucket full of ignition coils which will work regardless. B&S is very good about interchangeably. Large shops don't want to be bothered with used parts.
Check with your buddy's and see if they have a 8 to 10 HP briggs that is broken or go to a used mower place and get a Magnetron ignition coil. You can find them new for about 40 bucks.