Hi topfencer,
Probably not “good” ones no but there are some good sources for toppers in post #2 here that use a wide range of different materials. At your budget level you would probably be limited to some lower cost polyfoam toppers but of course with a topper it’s easy to replace them when they break down and there are some higher density options available for polyfoam in your budget range in the 1.8 lb range (although they may not include a cover).
Phoenix