I have a new set of Boyd’s I bought last year for a 336, but the realized they wouldn’t fit a 336y. I’d let them go very reasonably
I have purchased several 336 stock and forend sets from Boyd's, my favorite color is coyote brown with blued receiver and barrel. You may have to do some light sanding where the butt stock meets the receiver to get a "just right fit", this is not unusual when it comes to Marlin stocks.