Can you get an inexpensive shallow, wide pot ? Fill with regular garden soil, or bagged (real) soil , more like actual dirt, than "potting mix"?
You could then top with less than one full (more thin) layer, (or) a fairly sparsely covered layer with some of the more finely "crushed" gravel.
Sow your seeds as evenly as you can, over the top. Then sprinkle enough seed starting mix, peat moss, or as thin of a later of soil/dirt, as you can. Mist with water, & keep under the eave of the house, on the Southern most side, for as much winter sun exposure, that it can get.
Otherwise, you may sow them, & if that slope is steep enough, rains that much, or so often, they just may wash down that hill, before they germinate.
Usually that's about a months time, to germinate most of the regular Columbines. While the Rocky Mountain kind, may take awhile longer.
You might see them sprout in a couple months, as it is winter time, or mainly about by mid March. Depending on if your temperatures tend to remain cold, or just cool at night, & warmer (50 to 65F) in the day.