You will find here an emulator for the HP85B & HP86B/87 :

New release with FORTH support (only HP87 roms included) :

            (you need the previous one and overwrite any common files)

Here some informations about an HP85 recreation with an FPGA : FPGA HP85B

Here the next step, an HP86b+ with the same FPGA : FPGA HP86B

Some more emulators for android and windows here.