I definitely suggest just buying a new keezer. IMO I looked for so long and only saw nasty dirty ones for around 75 to 100 dollars. I bought a new 5.1 cu feet holiday from Loews at 129 using an old price tag someone had posted on here ( it was a lowes price tag from like 2009, but the guy matched me anyways.)
Youll save that much in electricity and peace of mind knowing that it'll run for a long time. I'd hate to see you build a killer keezer and have it fail because someone blew out the compressor.
I know it costs more, but shop around, look online, make some sales people say uncle!