I can't speak for the "best" year or model. I like my mid-80's RER 28" (Snapper RER 28085S) that was given to me by my father-in-law. Rebuilt, put a Honda on it and its been awesome for me. Does everything I've asked and ALOT more. Pull a Classic Cyclone rake too. Parts availability is about 80% or so. You might have to make the rest.
Oh, you can check FB Marketplace for tons of them. At least in my area. I'd look for cracks, rust, missing parts but overall, rebuildable.
Jim's FixIt videos are a great resource. Nothing against Jim but I find I have to put him on 1.25x or 1.50 but your mechanical ability will dictate that
He thoroughly explains everything. A++++