I write this from the standpoint of being a bus enthusiast / restore / resto-mod.. im always after parts for my old superior and carpenter.. and searching for a Wayne so i tend to migrate to spots with the *Bus* part of things..
Ohio
Mike and B sales - newcomerstown ohio. - BIG! buy whole busses or pieces parts.. typical busses are busses sent to them right pout of service. some are actually decent.. many are rusty.. parts for pretty much everything.. 90s-00s. lots of good hoods, mirrors, switches, seats, etc. possibly candidate for allison swaps.. they tend to try and sell newer busses whole, they get some which are too rusty.. I see stuf come through here with 3060s and AD2000s.. the lady owner doesnt like customers pulling their own parts.. the 2 guys that are usually in the trailer are "have at it"..
Warner Auto - mt sterling ohio - doing a classic bus restoration from the 70s / 80s? they have Superior , carpenter, Blue bird, wayne, Thomas, Ward , AmTran. most of their busses are early 90s and older. most drivetrain parts gone.. but lots of good glass, heaters, steering wheels, body trim.. some S-series, Ford B-series and Loadstar Hoods.. they also are a time-capsule of old cars.. ive seen perfect tasil lights and chrome bumpers for 60s cadillacs in there..
Starks wrecking - Miamisburg ohio - car junklyard with a few busses.. a few GMC chassis.. motors gone.. a few S-series and 3800 IH.. some busses still have original seats.. they have a couple Superior as well..
Myers - canfield Ohio - Mixture of busses.. seems like stuff doesnt stick around forever here.. they dont like to talk on the phone much.. best to just go.. good size and everything from 80s-00s.. ive even seen a couple nearly new busses that were crashed,, still had good Maxxforce motors intact..
there are others that some of my friends go to. but I havent gone to yet.. these above are my main go-to for junk bus parts.. yes Ohio / indiana / western PA, kentucky tends to be a mecca of wrecking yards.. .. nmy guess is because the average life of school busses in this area is relatively short due to High usage of road salt.. perfectly running busses in the bone yard with 6000 hours and 120k miles are not uncommon here.. however you might put your feet through the floors..
-Christopher