I work for Toyota parts distribution center in California and I have the ability to check every dealer in the nations inventory as well as all of Toyotas inventory at all the pdc's ( parts distribution center ) in the USA and I can honestly tell you I got the last one documented in inventory dealer or parts center , as for your question to what kind of proof : a source that has it , a phone # and a contact , I stand by my word 20 bucks , but you know my whole point is with our first gen trucks things are really coming down to the last ones trust me I'm almost done restoring a 89 4Runner and it's been 4 years of research for all my oem parts which is all I used