I have a Prusa MK3/4 enclosure & a box of the parts leftover from upgrading a Prusa i3 MK3S+ to MK3.9 to MK4S to Core One. It may be enough to build a MK3, not sure.
Includes the light & removable power supply addons but not the filter.
Local (Kansas City) pickup only.
https://kansascity.craigslist.org/ele/d/overland-park-original-prusa-mk4/7857386851.html