Yes, the Replacement Pin and Tether # P307 that you referenced has a ball bearing in the pin to keep it from sliding out.
I attached a picture that shows the pins pointed out on a Swagman XC Bike Rack # S64650. view full answer...
The Replacement Top Channel Cover for Thule AeroBlade Load Bars - 59" Long - Qty 1, # 852-5402-005 is the correct part for the Thule ARB60. The measurement accounts for the Replacement End Cap for Thule Aeroblade Load Bars, # 752-2867001 and # 752-2867002.
If you need the Replacement Bottom Channel Cover for Thule AeroBlade Load Bars - 14-1/4" Long - Qty 1, that part is # 852-4498-001. view full answer...