dealer only item? i think not. they are super common. trico is the oem maker they run 7.99 each. walmart sells anco for 3.48 each or pylon brand for 2.44. the pylon brand has been very good to me they clean well and are cheap and quiet.
Like Ford390 posted, Trico is a common shelf item in parts houses. The Trico 20-1 will fit my '04 RCab. Parts houses stopped stocking just the rubber insert because too many non-mechanics were getting the wrong insert and asking for replacement help. The Trico 20-1, or any other blade number costs little more than what rubber insert replacements used to cost.
Nevermind, I called the auto parts stores, and it's a dealer item and they don't just sell the refills.
Just for future refernce to others, they are $13 a side.
Advance Auto Parts has them, what you need is TRICO refill part # 45-200 thats the one that fit my 2004 F-150, it is just the rubber part, you don't need to replace the blade assembly. I replace them once a year.
I just replaced mine with the PIAA SPORZAs and they are AMAZING! It never streaks and its even has a built on spoilers on the blades to be more aerodynamic during high speeds. Anywho, best blades I have ever used.