From near Salisbury, UK.

Prise off the remains of the hose and clip with something like a flat head screwdriver.

New hose and clip are still available from Yamaha, and your local dealer should be able to order them. Sites like CMSNL (in Europe) and Partzilla (US) will give current part numbers. With the oil line, it will likely come in a fixed length that you cut to required size.

1960yblock...  it's likely not a 1975 year model DT125 if oil line goes to carb and not cylinder.  Check VIN to make sure.  1976 model had some unique parts so it's good to ID exactly what you have.

Best to use OEM hose and clips as already advised.

Thanks for the info, Gr8uncleal and MarkT. I got it pried off. As to the year, the manufacturers tag on the frame indicates 5/75 as the date of manufacture. The vin is 560-001091 and matches that on the engine, frame and tag.

560 prefix is a 1976 model DT125.

Frames for the North American markets (maybe others too, but not Europe/UK) had the date of manufacture shown on them and very often a frame was manufactured the year before it was actually used, and this is probably the case with your bike.

Here in the UK, for vehicles imported from North America, it often results in us being supplied with a registration (license) number for the year before a model was actually released by Yamaha. This is because the original number issued for a vehicle is based on either its date of first registration in its originating country, and for this you need the original logbook/license document, or the year of manufacture, which is taken from the date on the frame. So, a first year (1973) RD350 may well have a registration number based on the date of manufacture of the frame (1972).