The NSW State Archives search comes up with a Henry Randolph on the Assisted Immigrants Index, ship Francis Ridley, year 1849, place of arrival Port Phillip. The passenger list has Edward age 29 and Henry age 24 together, both farm labourers, Edward's birthplace Chipperly, Bucks, and Henry's "Austin Linton" (presumably Aston Clinton?).
https://www.ancestry.co.uk/interacti...=successSource