Amazon.com: Musiclily Pro 6mm to 10mm Vintage to Modern Sized Guitar Tuner Conversion Bushings Tuning Pegs Adapter Ferrules, Chrome (Set of 6) : Musical Instruments
Waverly guitar tuner conversion bushings, metric 10mm to US vintage fit set of 6 | eBay
12 Pcs Metal Guitar Conversion Bushings Ferrules for Vintage Tuning Keys Nickel | eBay