I'm kinda funny about my 2-strokes. I like to stick to the same oil the motor was broke in on.
But if you don't know what was in it, any TCW-3 oil will suffice. Costco has Quicksilver (Merc)oil for $11.79 a gallon. I've used that since 1987 without a problem.
If you switch to a synthetic, you might want to purge the old oil out of the system first. Some petroleum based oil isn't compatible with it.