JD Part number for 420 mower deck

Hi Guys! New to the board..... I spend a good amount of time on small engines of all types. I am currently looking for a mower deck for an older JD 420 garden tractor. I found a deck on CL but I can't seem to find a listing of JD part numbers tht match it? Anyways, the part number on the unit is hard to read but I think it's M00130505920? The guy doesn't know what it fits...... and I have never worked on a 420 other than the engines. I can't tell for sure if it will work or not? Any thoughts? I dont want to drive 4 hrs and waste my time....... thanks!

a 420 would have had a 50" or a 60" deck

the 50" deck model # would start - "M01012X"
the 60" deck model # would start -"M00272" or "M00273"