Since I need True RMS for power amp gain calibration, I also need the temp sensor for power amp repair, I just bought the 179 with additional electronic probes, original fluke case and the thermal probe in a Like New condition for $140 shipped on eBay.
Good thing you recognized the need for True RMS and didn't pick the Fluke 17B or 77IV. The temperature probe is insanely expensive ($36 list price) if you have to buy it separate.
I estimate that only 5% of the ebay auctions include the probe for models that support temperature (87V, 179, 187, etc).
I lucked out and found one (new) for $6. The seller had 20 to sell, but I wasn't sure of the quality or if it was the real thing so I only ordered one with the intent of ordering more if I was happy. Since it came from China, it took about 3.5 weeks to arrive and I determined it was a real Fluke (to my eyes). When I went to go order more, the seller raised the price to $35. However, 2 other people noticed the original $6 pricing and also placed an order.