I bought the OPL3LPT from Serda Shop: OPL3LPT

It's an Adlib compatible add-on for PC parallel (printer) port.

To make it work, I had to:

• Make a AT keyboard to USB Mini power cable adapter
• Download latest oplutil: https://github.com/pdewacht/adlipt/releases

EMM386 was needed. To load it, I had to edit config.sys on my Toshiba T3200SXC:

device=c:\windows\himem.sys
device=c:\windows\emm386.exe noems

Then I could load ADLIPT

cd oplutil
adlipt.exe

And Lemmings was running fine with Adlib sound.