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I find the fastest places to get specs are from distributor websites like digikey or mouser which have filters for each category such as Optoelectronics. each item has a datasheet.
3 pin Rx are smart AGC, tuned detectors used for remote controls and longer distance communication at slow rates.
2 pin PD's are very linear matched diodes that when reverse biased supply current over many decades of light intensity but require high gain amplifiers, signal conditioning and tend to be used for either daylight sensing or short range interruptor or reflector detection.
The pulsed carrier and AGC of the smart Rx makes it more sensitive to pulsed IR carrier and more immune to interference from other light sources.
However 2 pin PD's and 3 pin Rx's also come with black daylight sensing filtered plastic which allow IR to pass thru.