The Scuba Museum has the VDH rings and stainless rings are on Amazon and elsewhere.
The red hoses are the correct, historic size, your unit may have been shipped with the VDH flex hoses, edpm material, and they were slightly larger if I recall requiring a larger ring. (note that when ordering on the page linked above in product descriptions)
The red hoses are the correct, historic size, your unit may have been shipped with the VDH flex hoses, edpm material, and they were slightly larger if I recall requiring a larger ring. (note that when ordering on the page linked above in product descriptions)