Well, having replaced fans on one of my video cards recently, I'll tell you, I'm betting the fans on your windforce are available for purchase and I'm betting they're compatible with fans on most of the current generation of windforce coolers. That being said, I'm also betting that finding a "better" fan that fits your heatsink is not going to happen. Seeing as how you're using a 1050TI, I'd recommend you stick with the stock fans. It's not a high power/high heat GPU, "better" fans are not really going to get you any further up the performance ladder. Getting a good TIM might help you get a few degrees cooler from where you're at now, and that might be worth a few hz on the boost(*shrug, it's a big maybe).