Remember when SSDs were cost prohibitive for the most part? Those days are long gone, and driving that point home is this deal for HP's 500GB EX900 SSD. You can snag it from Staples for just $52.99 when using coupon code 45242 at checkout.
The coupon code shaves $15 off purchases of $60 of more. In this case, the 500GB is listed at $67.99. That's already a fair price, but the discount makes it even better.
As far as entering coupon codes go, it's a slightly tricky process—once you head over to your cart, click the 'Apply/edit coupons' link in the order summary, then enter the coupon code. The discount still won't be visible, which at first made me think it was invalid. However, the discount should finally show up you once you've proceeded to the billing page.
Looking at Newegg's collection of SSDs, prices for 500GB-class models start at around $60 and go up from there. Many of the lesser expensive ones are 2.5-inch drives with a SATA 6Gbps interface, with read and write speeds in the 500MB/s range.
HP's EX900 is an M.2 form factor drive with a faster NVMe interface. It is rated to deliver read and write speeds of up to 2,100MB/s and 1,500MB/s, respectively. You don't really need the added speed of an NVMe SSD versus a SATA SSD for gaming, though for other tasks (like transferring large files), it makes a difference. And since it's also cheaper, this one is easy to recommend in 500GB territory.