OTAM.
I checked the Winegard catalog and the Winegard web site but do not see a model PR-888. There is a PR-8800 which is an 8-bay bow-tie. An 8-bay bow tie antenna is a high-gain UHF antenna. For 50 mile reception with an attic antenna, you will definitely need a high gain antenna and a pre-amplifier. Since you need to receive stations from different directions, you will also need a rotator or 2 antennas with a switch. Also you will need to verify if you do not need to receive any VHF stations. Otherwise you will need a VHF/UHF antenna(s).
I am using an 8-bay bowtie antenna in my attic and get excellent reception with stations at 33 miles. I have a large attic space and actually have a VHF and UHF antenna on a wooden dowel with an antenna rotator. With a rotator you really need a great deal of attic space. I get excellent HDTV reception for one station which is just under 70 miles away! This means you have a reasonable chance to get good reception at 50 miles. It all depends on the terrain/obstacles between you and the transmitters and also the transmitter power for your stations.
I would suggest that you give it a try. You could get an antenna and just string a temporary cable to the attic and see what happens. Get an assistant to monitor the DTV signal level/quality indicator while you move the antenna around in the attic. I use cheap kiddie 2-way radios for this. Cell phones work well too. Even if the antenna does not work at all, hang onto it because many DTV stations are not yet operating at full power, if at all. Also, you may move someday and find yourself in a location where an antenna will work. I have been using the same UHF antenna for over 25 years! A good TV antenna costs less than most people spend on satellite/cable for a month or two!
Good luck.
DonP