Equipment to create "colorized" DWDM signals from white light?

So I've a DWDM project that has some equipment in scope that doesn't support any DWDM transceivers so I need a device that coverts the white light to my channelized DWDM signal to push into my Muxes.

I know Cisco has the ONS line that can do this but they're kind of pricey. What other options are out there to convert white light into channelized DWDM signals? Does anyone have a vendor or product they would recommend? Can I get standard 80km out of these?

I have a lot of enterprise/city campus WDM experience but I've always used single channel transceivers that plug directly into my equipment.