These are all the type 4 aftermarket remotes. Most of them are discontinued and some are still available. Others that are still available can be used as a replacement remote since all type 4 remotes are interchangeable.
Aftermarket remotes only works on aftermarket systems. Programming these remotes involves pressing/toggling a valet button/switch to activate programming mode. If your vehicle's system was installed without the valet switch/button you can order one and install it to make it easier to do the programming.