Hi poorwithgoodcredit,
Just in case you haven’t read it yet … the first place I would start is the mattress shopping tutorial here which has all the basic information, steps, and guidelines that can help you make the best possible choice inside your budget range and that fits all the criteria that are important to you.
Organic latex mattresses tend to be more costly than non organic latex mattresses but in many cases people who are looking for “organic” are really looking for “safe” materials. There is more information in post #2 here that can help you decide on which types of materials (or types of latex) you are most comfortable having in your mattress.
Some of the lower budget latex and latex hybrid options I’m aware of are also listed in posts #3 and #4 here.
If you let me know your city or zip code I’d also be happy to let you know about any of the better options or possibilities I’m aware of in your area as well and some of these may have financing available if you decide to purchase a mattress where you need it.
Phoenix