Finding replacement PNP transistors
It's not that easy. Which characteristics of a transistor are important isn't an universal thing – it depends on what the transistor is used for.
So, you'll need to analyze what configuration the transistor is used for, and what the critical characteristic is. For example, when desiging a feedback amplifier, a high-as-possible amplification and a low-as-possible base-collector voltage might be desirable, but that doesn't help you if the external circuitry that you're stuck with is optimized for something else. And it doesn't help at all because not every transistor is used as that – often, limited gain is factored into the design e.g. to ensure stability.