I've rebuilt a couple Massey plows in the past 3 years. (#66, 2X14", CAT I and a #74, 3X16", CAT II) I was able to get ALL the wear parts through Massey Ferguson dealer. (Landslides, shins, shares, moldboards, coverboards.) Cost was about $145 per bottom, but OEM parts fit well and wear better than most cheap aftermarket parts.
Depending on where you're at, Kvernaland plows (and parts are virtually nonexistant. Everything here in my area is no till now. A few tobacco growers still plow, but most have gone to rototillers. The dealers are still vaguely familiar with older plows, but no one buys new plows here, and Kvernaland is "new" to the central US.