Using Milk Chocolate instead of unsweetened chocolate in a pie
Milk chocolate is usually made for eating, not for baking. In any case, even if you are using a milk chocolate that is meant for baking, you need more than milk chocolate and eggs to make a chocolate silk pie.

Your desired result is light, smooth and consistent throughout. To get there you need to add volume in the form of air, typically by folding in whipped cream, but also by making a nice light custard of the eggs over a double boiler. You can't just mix the eggs into the chocolate and expect to get the right texture.

If you can determine the proportion of sugar to cocoa to milk solids in your chocolate, and if there is not too much else in the chocolate altering its texture, you should be able to tell if you are close enough to the proportions of your original recipe to pull it off.

Please share your result with us if you tried this for Christmas, or do in the future.