Wix has a filter look up site that lists many equivalents. wixfilters.com
The Wix filter for the Kohler 12-050-01 is a 51056.
KOHLER 1205001
Baldwin - B10140 Fram - PH8172 Kohler - 1205001 B&S - 492932
Fram makes a poor quality filter which I advise you to not buy. Purolator on the other hand makes an excellent high quality filter which costs no more than a Fram. Your Kohler filter 1205001 cross references to a Purolator L35310 sold at Advance Auto Parts and some Walmart stores. I recommend you use only synthetic oil in any air cooled engine.
12-050-01 may be a better number to search oil filter suppliers for a substitute. The Kohler oil filter 12-050-01 was superceeded to 12 050 01-S1. Fram still has the old number and it crosses to Fram filter PH8172
Equivalent to 052-050-02
That would be a Fram PH8172
PH3614
PH4967. Fram specifically says the Kohler 7.3E uses this filter
sfwe
That is a NAPA 1348.
I use Hastings filters. The Hasting replacement is a LF157.
Wix has a filter look up site that lists many equivalents. wixfilters.com The Wix filter for the Kohler 12-050-01 is a 51056.