Hi I did something like this a few companies ago. We looked at some activities we paid outsiders to do. For example speak on a webinar and using those as a benchmark come to an agreement internally on what is the value of different acts of advocacy. Once you get a few, the others are easy. So a full case study might be work 10k and a quote for the web page 2k. It can get more sophisticated over time. So a case study that gets 1,000 download after 6 months is worth more than one the only get 100.
I am surprised more organizations don't use this as a way to think of the value advocacy. Companies are so focused on attribution which is really hard and advocacy usually ends up on the short end of that stick.