I've got some syringes that I use for filling oil lines on 2-strokes. You may be able to find appropriately sized syringes at your local pharmacist, however, I just received an ad from Banggood offering a set for $5.

https://www.banggood.com/60PcsSet-Di...r_warehouse=CN

You can get a lifetime supply of syringes of various sizes, lengths, etc. Great not only for pre-oiling the oil lines, but putting just a drop of oil in a hard to reach place. You can have different ones for 2-stroke oil, 4-stroke oil, penetrating oil, etc.