While there are vertical antennas for HF, you're fighting a losing battle, since the signals are horizontally polarized. Height is not as important with HF as it is with the VHF/UHF bands. Lenth of wire and antenna design is a lot more important. Now, if you had two fifty foot masts about 200 feet apart, there are some killer long wire antennas you could put up.
Actually it's quite difficult to determine the polarization of a signal on HF, as it can and does change as it refracts off the ionosphere. Verticals are more sensitive to signals coming in at lower angles, but the flip side is that they're very prone to man made noise sources.
Even that mast can act as a HF antenna (pretty good one, too - at 50 foot you're right around a quarter wave at 60m). Yes, the PAR has gotten numerous great reviews, but don't forget some of the DIY types which are in the wiki.