I have searched our PegaSupport database and have seen this same request made over and over; that's probably the impetus behind the solution being incorporated into the 7.3 product. Unfortunately, as far as I can tell, there does not appear to be a single customer who was successful in implementing this in a lower product version.
I do see one customer back in 2016 who appears to have engaged Pega Consulting to implement this. If you wish, I can try to determine if they were successful in achieving their goal. Be aware that if they were, the best I could do would be to offer you the same option of having Pega Consulting (in a fee-based interaction) build the same for you.