Hi AustinFromWA,
You are certainly looking at some good options 
As far as your “comfort questions” or the “suitability” of a mattress and how any of their mattresses may feel or perform for you in terms or PPP (Posture and alignment, Pressure relief, and Personal preferences) … when you can’t test a mattress in person then the best approach is always a more detailed conversation with the manufacturer who can find out more information about your body type, sleeping positions, preferences, and some history of other mattresses you have done well with or any local testing you have done and help “talk you through” which of their many choices may work best for you (see mattress firmness/comfort levels in post #2 here). They will have more knowledge and experience with their mattresses and helping their customers to “match” the different options they have than anyone else because they help match customers to mattresses all day every day.
As far as the quality of the materials in the mattresses you are looking at … all of them use good quality materials and there are no weak links in their designs. Most of the differences between them would be based on your personal preferences and how different types of latex and designs “feel” compared to others.
Synthetic Dunlop is a little less resilient and “supportive” than 100% natural Dunlop (it doesn’t get firmer as quickly as natural Dunlop as you sink into it more deeply) and in the firmer versions (C4 and C5) they are likely to be a little less durable than other types of latex in the same firmness level as well but like any type or blend of latex they are still a high quality and durable material relative to other types of foam.
I also agree with magpie that if you are looking at a smaller size that a twin XL would probably be a good idea.
A twin size also makes your $1000 budget much more reasonable and would give you quite a number of options including the ones that jermy4 mentioned. There are also some good “budget” sources for latex and latex hybrid mattresses in posts #3 and #4 here but these were for a queen under $1000 so you would have more choices than the options that were listed there.
Once you have had a more detailed conversation with each of the manufacturers you are considering and have narrowed down your choices at each one to a single mattress then you will be in a much better position to make a final choice (see post #2 here) based on all the objective, subjective, and intangible parts of your personal value equation that are most important to you.
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