craigslist??
JD400 series: 400, 420, 425,445,455. A couple are diesel and will give you longer life. Can be had with 3ph and rear pto. all have hydraulics. Best garden tractors ever made.
Also JD4110 or 2305
Kubota bx series
Simplicity.
Ford 1200
Gravely professional series.
You might try www.tractorhouse.com and Used Tractors & Other Farm Equipment for Sale at IRONsearch.com and Home :: WebFarmer and Used Farm Equipment from agriculturalsearch.com offers, Combines, haying, used tractors, used machinery by John Deere, Ford, Kubota, Case, NH, AGCO, used combines,used haying equipment,used farm tractors and Used Farm & Agricultural Equipment - John Deere MachineFinder but I think you will find that once you get west of Kansas it becomes "Slim Pickens" for good used equipment.
There is a 420 with an Onan engine for sale locally. it has a belly mower, 3 pt, rear PTO, 3 hydraulic hook-ups for attachemnts. The pictures look like it is clean, but I don't know the hours on the engine. He's asking $2200 firm
Are the Onan engines reliable? How many hours are they good for if maintained? I understand they are costly to repair.
Any other problems?