The first question is how much are you willing to spend? And what other uses might the mower have?  My father and brother in law set and talk about their Sears Craftsman tractors and how great they are.  I have trouble using tractor and Sears in the same sentence. But I mow a LOT more than they do and I am mowing yards, not lawns.

It sounds like you don't want a "lawn" mower, but a "yard" or "lot" mower.  Could something like an 8N Ford with a small rotary cutter do the job?  If you keep the blades sharp it will probably do an acceptable cutting job if you only mow it 3 times a year anyway. But it has to be an open enough area that a tractor that size can maneuver.

On the For Sale pages Pat has a Land Pride ZTR for sale that is a "fixer upper" ( see it at http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=280350346994 ) that would probably doa wonderful job if you want to work on it a bit. Pat is a regular here and I've bought a thing or two from him.  I'd trust his description to be exactly what it says.

Another possibility is looking around for something like  an A or B Farmall or a little Allis Chalmers wth a mower deck under it

They seem to have fallen out of favor with people wanting new tractors with hydraulics, 4 wheel drive, etc.  If you are going around obstacles a zero turn will out perform them by an incredible amount.  But for basic straight flat mowing they are still tough to beat.

edit: You asked about specifics.  I'd avoid a "cone drive" Dixon.  They can be had cheap ... but can be a mechanical headache.  I ... well, had another thought but it flew away before I could grab it... maybe later