Finding sound cards for your retro PC setup is hard. Used sound cards can easily run you more than $100.

PicoGUS is an 8-bit ISA sound card and CD-ROM drive emulation on the Raspberry Pi Pico’s RP2040 microcontroller. PicoGUS can emulate a wide variety of sound cards as connect your old IDE CD-ROM drives:

• Gravis Ultrasound (GUS) – the primary focus of PicoGUS, hence the name
• Sound Blaster 16 (OPL3) / Sound Blaster Pro 2 (OPL3) / AdLib (OPL2)
• MPU-401 (with intelligent mode) – outputs MIDI data on 3.5mm MIDI TRS connector
• Tandy 3-voice
• CMS/Game Blaster
• Game port joystick
• Panasonic/MKE CD-ROM

It’s not quite perfect (see the compatibility list), but

Available at Joe’s Computer Museum Shop for $50