Just talked to the Rep at Motion Ind. and Bunting, Garlock and KS (Permaglide(R) are all the same material, just a big price difference. They have thousands in stock!
You can go into
http://www.applied.com and look up the specs on all sorts of bushings. This is the spec for the Garlock bushing:
# Steel backing gives DU its exceptionally high load carrying capacity; thin, compact design; excellent heat dissipation; and dimensional and structural rigidity.
# Porous bronze innerstructure: This comprises a nominal 0.010 inch (0.25 mm) thick layer of carefully sized bearing quality bronze powder which is sintered onto the steel backing. This porous structure is impregnated with a homogeneous mixture of PTFE (polytetrafluoroethylene) and lead. In addition to providing maximum thermal conductivity away from the bearing surface, this unique bronze innerstructure also serves as a reservoir for the PTFE-lead mixture.
# PTFE-lead overlay: This low friction overlay, approximately 0.001 inch (0.025 mm) thick, provides an excellent initial transfer film which effectively coats the mating surface of the bearing assembly, forming an oxide type solid lubricant film. As this film is depleted, the relative motion of the mating surface continues to draw material from the porous bronze layer. When conditions are severe, the feed of lubrication is increased. The peaks of porous bronze coming in contact with the mating surface generate localized heat and, due to the high thermal expansion rate of the PTFE, force additional lubricant to the bearing surface. The relative motion of the mating parts wipes the lubricant over the interface, continuously restoring the low friction surface film.
# Loads - P: dynamic pressures up to 20,000 psi (140 N/mm2) assuring high load carrying capacity and excellent resistance to shock loading
# Speeds - V: Speeds up to 1000 fpm (5m/s) without lubrication; 2000 fpm (10 m/s) with lubrication
# PVs to 50,000 psi-fpm (1.75 N/mm² x m/s) for continuous operation, 100,000 psi-fpm (3.50 N/mm² x m/s) for short-term use. In actual operation, DU bearings have been successfully used at levels which approach 3,000,000 psi-fpm (105 N/mm² x m/s) lubricated.
# Temperatures from -328 °F to 536 °F (-200 °C to 280 °C) making it suitable for use in applications well beyond the scope of most liquid lubricants
# Ideal for all types of rotating, oscillating, sliding motion, and both radial and thrust loading
# Can be used totally dry, fully lubricated, or with intermittent lubrication and can be used in the presence of many industrial liquids