I do not know if the districts changed between census years and I do not have a map.
In 1851 Rushen districts were (Brian please correct if I am mistaken):
District 1 Scholaby. West of Port Erin
District 2 Surby. North East of Port Erin
District 3 Bradda. North of Port Erin
District 4 How(e). South of Port Ern