The same hobby shop that sold you your Morgan Fuel product (Coolpower) can sell you castor oil, coolpower synthetic oil, or their 70/30 castor blend.
http://www.morganfuel.com/homebrew.htm
FHS sells a racing castor oil and other types of 2 stroke methanol compatible oils.
http://members.aol.com/FHSoil/FHSbrochure.html
THis website sells Klotz benol racing castor and is what I used in the past. Any hobby or kart racing store should be able to get Klotz oils.
http://www.prop-shop.com/FEFUEL.HTM
http://gcbmrc.com/klotz_lubricants.htm
http://www.wahlracing.com/lubricants...park_plugs.htm
http://www.pro-flo.com/klotz_oils.htm