I agree with Paul, just do small batches with printcarrier you can get them in 3 days.
I've Never seen a riso leaflet that looks proffesional and not homemade.
What you need is a template made by a designer with empty sections that you can open in MS paint and use its text boxes to put different offers
I have STOP PRESS!! Latest news & offers from Henry Halliday then 3 blank boxes. I fill them with different offers