Appliance Repairman

I live in a basement apt and have a Eaton Viking range (yes, very old). The stove works great but the bottom element in the oven stopped working. I verified it was not the fuse and knew it would require a professional. My landlord said he would look into getting a refurbished range and just replace the old one. I did some research and it looked like the average price would be $500 for a refurbished 22" range. So, thinking I was doing my landlord a favor, I went online and found Appliance Repair Guys. Surely it would be cheaper to just repair it right? When I called I was told it would be $80 to come out to diagnose the problem. The repair itself would then include the $80. Okay, sounds good so far. So I agreed and they booked for the technician to come out the next day.
When the technician arrived, within 5 mins he told me it would be an automatic $280 (-$20 "inconvenience rebate" for switching the time of day the tech would come) for a total of $293.80 taxes incl. Just 20 mins later, after testing wires, signals and sensors, he told me it was the relay switch that needed to be replaced and once the part was in he'd charge me for the part but not the installation. I asked him how much for the part and he estimated anywhere between $50 and $200 :-S So I told him okay and to call me back with the price and how long it would take. He said he would personally call me back that night. He also assured me that this range is way better than any new ones made these days and that once this problem was fixed it could last indefinitely.
Well, big surprise, no call that night and no call then next night. The weekend passed and still no call. I finally called them on the Monday morning. They said they were looking for the part but since its such an old unit it may not be available but they will call me back. (oddly, they encouraged me to call back as well). I then did a quick Google search on a relay for an Eaton Viking and was able to find a bunch of hits very quickly. So why was this taking so long? They are supposed to be the experts on this stuff!!
So I just called back now... what a major disappointment! The customer service agent told me the unit is so old the part may not be available. Then she said we are still trying to find the part and will call me back when they can. I told her I don't understand why I paid $300 to basically diagnose the problem!! That's the labor cost she said, to diagnose the problem. What??? I am VERY disappointed. And now, because it was me that called them in and not my landlord, I feel obligated to pay for the mistake even though my very nice landlord said he would split it with me. He wasn't happy at first because he said he could get a refurbished one for $250. But this was my stupid mistake to call the Appliance Repair Guys in the first place. Please DO NOT make the same mistake I made. NEVER use these guys unless you have $300 to throw away!