I am looking for the water pump pulley for a 4.5 conversion on a 69 with 4" Pump

Parts Recommendation
1

The 68 and earlier and early 1969-1/2 used the 4" water pump. This pulley allows you to use the 4-1/2" water pump from 1969 and up.

https://butlerperformance.com/search.html?q=plw3