Try the 4895's (H & IMR) in the same quantities you are thinking for 4064. I have used 4895 a lot with cast bullets from 250 to 287 grains. Not hard to get excellent accuracy with an air cooled WW bullet in the 1850-2000 range. My bullets are Lyman 358318 and NOE clones and Lyman 358009. Use a quality lube like Carnauba Red or similar and size .002 larger than bore to start.