I have both 1980 and 1983 240's. I recently purchased locking gas caps for them at the local chain parts store. I think they are made by Stant - at least there is a large "S" on the top of it. These both used the same key and were reasonably priced at maybe $10 each. But they have really turned out to be junk. In fact, my wife recently returned from a road trip to Oregon - where they insist that drivers cannot pump their own gas - to find that after the fill-up down there the lock tumbler was completely gone. Luckily, I was able to figure out how to remove it with a screw driver and still had to original cap. But I have seen this almost happen to my other unit as well.

So my question is, where can I find something decent to do this job? Brand, model number, where to buy are all appreciated. Amazon shows an AC Delco 12F20L but has no photo so I cannot tell if there is any real difference between that and the one I have now. Thanks for your suggestions.