You could try
www.boatsetup.com there are about 4 Evinrude junkeys on this site that should able to help you, some of them are dealers and some work in Evinrude, and they know pretty muct every thing.......
If the 99 Evinrude you are looking at is a FICHT...... Run very quickly away from it, as in 99 the company was in trouble, and build quility is crap, and problems are frequent, IF its normal 2 stroke it should be ok.... But I dont think it worth 3K, there would be very few buyers for that type of engine, and its going to be slow with the big gearbox etc......
97-00 FICHT 150,175 are a disaster
97-99 FICHT 200,225 are ok ish
After 00-01 they are got a whole lot better.... but still a bad reputation.....