I have the same problem with a new choke cable. I don't know where you can buy one that has a stop but I do have a workable solution. I use a small piece of rubber vacuum hose cut to the same length as the distance required to hold the choke fully open. I slit it length wise and push it it place to hold the choke open. When it is time to push the choke back in, I pull the hose back onto the choke knob. May not be what you are looking for but can work until you find a better solution. George