Selle Italia and WTB both offer a saddle loaner program to shops.

They sell a discounted and basic selection of all their shapes that the shop can loan to you until you decide which shape works best, then you can buy any quality level you like, add ti rails, leather or vinyl, etc.

Call around to see if any of your local shops offer the program and what their policies are. Some shops offer an exchange for saddles whether they use these programs or not.