You could probably still find the color in stores or online, at least for now? In the meantime you could try searching for something else. It's a little bit of homework but here goes.
Revlon is owned by MacAndrews & Forbes. A little trick I've used in the past is to look at who owns a brand. Afterward, I look at all the other brands that the companies owns...and chances are there's a product similar to what I use (similar ingredients) and one of them is always cheaper. So I go for the cheapest, and have the same results.
So in your case, I would check out all the brands M&F currently own. I realize it's way more delicate because color is so specific, but it's worth a shot. Try looking into Almay, Philosophy skincare, Sinful Colors, Charlie fragrances, Mitchum, Ultima II Cosmetics and Gatineau skincare. I don't color my hair so I don't know if these other brands even offer hair coloring products, but it's worth a try. You can also compare ingredients in-between in the Revlon color lines. You might be surprised!