I made an add-on for this a while ago. Since it was made for my own server and not intended to be released, the weapons list is hard coded in the script, but its not hard to change.
Just open server.cs and change the lines at top to match the itemName of the weapons you want. In order to get the item names, you can either open the script file for the weapon you're looking for and ctrl-f search for "ItemData' or start a server, equip the weapon, and in console type
"echo(findclientbyname("your name").player.getMountedImage(0).item);"
You can add or remove lines if you need more/less, but you need at least two unique weapons listed or the game will crash
DownloadIt might be doable with VCE but I just did it in a way I already know