All I could locate is below. It might be a good start.
https://www.boss.info/us/products/dd-500/
But is for Model Boss OD-1 OverDrive
• IC: RC3403ADB, uPC4741C, NJM4558D, uPC4558C, uPC4558C, TL4558P, JRC4558D, JRC4558DD, JRC4558DC or C4558C (depending on your model)
https://www.digikey.com/short/zh892z What we have for op amps
• Q1: 2SK30ATM-Y (N-channel JFET transistor)
• Q2: 2SK30ATM-GR (N-channel JFET transistor)
• Q3, Q4, Q5: 2SC945-P 2SC1815-Y (NPN silicon transistors)
• Q6, Q7: 2SC732TM-GR (NPN silicon transistors)
• D1: RD11EB-3 (500mW 11V Zener diode)
• D2: RD5.1EB-3 (500mW 5.1V Zener diode)
• D3-D10: 1S2473 or 1S1588 (switching diodes)
• D11: SLP135B (LED)