Just came up with this idea and found this https://www.seriousgmod.com/threads/detective-wep-station.4714/#post-37046 So I'm going to make my own version of the idea. Similar to the Health station, a dispensary unit that gives out a limited supply of ammo by pressing E on it. The Ammo will run out after so much is given. Will help especially on maps that are low on ammo. Possibly make it so that the detective cannot buy both a health station and an Ammo Dispenser, has to be one or the other. To keep it balanced. Not too sure about this though.
I've used this specific item in Yashimare's server, it's perfect. Only problem is restricting the amount of ammo available, but you could probably have a word with him about that. Similarly, there's a briefcase which does the same, but doesn't have an in-game pointshop picture which could be fixed.