Amazon.com: Slot Loading Portable External Blu-ray DVD Players, for Windows 10 2-in-1 15 17 Inch Touch Screen Laptop & Desktop Computer, Super Multi Blue-ray Player 8X DVD+-R DL CD-RW Burner Optical Drive
Here's something interesting: a slot-loading 5.25" optical drive made by GoldStar : r/vintagecomputing
Dell GSA-S10N - 8X DVD+RW Slot-Loading IDE Burner Drive - CPU Medics
computer building - Slot load DVD burner options for standard desktop case - Super User
Meet the New 5.25" Optical Drive Standard: Slimmer, Slot-loading
Amazon.com: External CD DVD Drive, USB 3.0 High Speed Data Transmission External Slot-Load DVD Burner CD Driver External Optical Drive for Laptop/Windows/Desktop : Electronics
Configure PC w/ Plextor 16x DVD-RW Dual Layer Slot-Loading (black)
Amazon.com: Internal 6X Blu-ray Burner 12.7mm Slot Loading SATA Optical Drive, for UJ-265 UJ265, BD-RE DL TL QL BDXL 50GB 100GB Blue-ray Disc 8X DVD RW Writer for Dell HP Laptop iMac