Hi shan808,
The better options or possibilities I’m aware of in the Los Angeles region are listed in post #2 here but I’m not sure which of them carry toppers so I would check their websites and/or call first to make sure that they carry the type of toppers that you are interested in testing before you go there.
I would also keep in mind that the mattress under a topper will also make a difference in how the combination feels for you so while local testing can help you decide on the types of materials you tend to prefer and can give you some sense of different firmness levels … when you can’t test the specific combination in person then the return or exchange policies would likely become a more important factor in your purchase so if you purchase a topper that doesn’t work out as well as you hoped for that you still have additioinal options remaining.
The listing says that the topper is 100% natural Dunlop latex which is a high quality and durable material. If it really is 4.75 lbs density then it would almost certainly be firmer than the 16 - 18 ILD they have listed which would generally be considered to be soft (it would more likely be in the mid/high 20’s). You can see some examples of approximate firmness levels and ILD’s for different densities of 100% natural Dunlop latex in post #2 here.
The 2" thickness seems reasonable but this may be firmer than you expect (if the density is correct) particularly with your lower body weight.
If you did decide to try this I would make sure that you are clear about their return policy and any costs involved so that you are comfortable with the risk in making any topper purchase where you can’t test the combination in person before you buy it.
There is also more about how Dunlop latex feels compared to Talalay latex in post #7 here.
Phoenix