BG10 drag knob

[JasonGotaProblem]

A friend picked up a BG10 for a crazy deal ($6!) but it's missing a drag knob and also a handle screw cover. Are there any other daiwa reels that have parts that might interchange? I saw a drag knob on eBay for $10 I may tell him he has to get that, but if one of my parts reels from the bin would fit the bill I'd rather go that route.