You should be able to find an older 2 cycle mower (we always used the Lawn Boy Iron Horse mowers for the pond banks when I was growing up - used the same mower every week to mow the pond bank for 15 years) at a garage sale/auction/etc. A 4 stroke won't last on much of an angle, as indicated above by others.

Dale

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"When tempted to fight fire with fire, remember that the Fire Department usually uses water." - anonymous