The first photo does look like an assassin snail. In addition to 2 thin antennae, assassins have a thicker tube as shown in your photo that sticks out as they move around. MTS don't have this tube and instead have something that is more obviously identified as a head/mouth.
The first egg photo doesn't look like an assassin snail egg. The case's edges seem too round compared to what I've seen. Assassin snail eggs look like a see-through rectangular packet with a solid round egg in it. The second egg photo doesn't have enough detail for me to comment on.
Sorry I don't have a definitive answer for you. On the upside, assassins are in demand in Toronto so you should be able to sell them. I'd buy small ones myself.