I threw out a 20 inch 505 victa the other day ,it had a broken base where the handle bolted on but could have been repaired.
Didn't know you were still looking for a base Norm.
The 505 Professional mowers are 20 inch and can be pushed if the Sp doesn't work ,this one was given to me last week with another 2 stroke mower ,I was talking to a guy that said he just bought a house and the owner left a couple of old mowers he didn't want so I said Yeah I'll take them. Wasn't much wrong with them as both run good with minimal work.
Two Victa tornado mowers welded together ,it should be nice and light to push.