Within my club I got a ton of crap for doing the groundwork for doing an order for Soar singlets so that marathoners wouldn't need to worry about their nipples being sanded away by the terrible old vests we have (this was an optional opt-in purchase of the exact same design). Also got shot down for suggesting we advertise specific paces for club runs rather than letting people race each other, because the Sunday club run obviously has to be at marathon pace as thats how they did it in the 80s.
There is nothing stopping you just making your own vests yourself. I know this happens at our club.
I used to do my Sunday runs over the heath and they were insanely fast with our group. I wish I knew that it was ok to run slower.