We purchased our blinds and soft light shades from JC Penney, they had the best price. You can order the hold downs but we replaced them and use Velcro strips instead. There are a couple ways to get by the latches. One is to just let them stick through the blinds. The second is to build a shadow box around the window frame so the blinds will not rest against the window and give clearance to the latches. You may prefer this arrangement since it gives a neat appearance to the sides and completely closes them off giving you more privacy. Plus you do not need the annoying hold downs and the blinds will operate much easier.
1994 30' Excella 1000, Chummy III- Ford Excursion- 7.3 Turbo-diesel