Recently picked up a Sunstar with a 16HP Kohler. Model # 1691357. Starting to go over it and do the maintenance that it needs.The tractor only has 550 hours according to the meter but the hydro oil and filter was replaced in 2008. Thought that I would replace it again and it calls for filter # 1671234sm which sells for about $60. Being a bit of a tightwad is there a less costly filter available? Can't seem to find one.