There are loads available. Not sure about "latexy" finish though. What you may have heard is people saying "we could latex the floor" because the powders are often mixed with a solution of latex (and I wish I could remember why…some did tell me once) before spreading them out.
If it's a big old area, you'll need a lot, and don't think you just mix it, pour it and let it do the work for you. You will have to spread it so a trowel will be needed and you need to work quickly enough, depending on the product you use. They start curing quite quickly.
And it's unlikely you'll get one that doesn't need painting – they tend to have quite dusty finishes.
Avoid the B&Q stuff.